Commit Graph

169 Commits

Author SHA1 Message Date
Richard Henderson
09cbd50198 target/arm: Convert jazelle from feature bit to isar1 test
Having V6 alone imply jazelle was wrong for cortex-m0.
Change to an assertion for V6 & !M.

This was harmless, because the only place we tested ARM_FEATURE_JAZELLE
was for 'bxj' in disas_arm(), which is unreachable for M-profile cores.

Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20181016223115.24100-6-richard.henderson@linaro.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-10-24 07:50:17 +01:00
Richard Henderson
7e0cf8b47f target/arm: Convert division from feature bits to isar0 tests
Both arm and thumb2 division are controlled by the same ISAR field,
which takes care of the arm implies thumb case.  Having M imply
thumb2 division was wrong for cortex-m0, which is v6m and does not
have thumb2 at all, much less thumb2 division.

Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20181016223115.24100-5-richard.henderson@linaro.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-10-24 07:50:16 +01:00
Richard Henderson
962fcbf2ef target/arm: Convert v8 extensions from feature bits to isar tests
Most of the v8 extensions are self-contained within the ISAR
registers and are not implied by other feature bits, which
makes them the easiest to convert.

Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20181016223115.24100-4-richard.henderson@linaro.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-10-24 07:50:16 +01:00
Peter Maydell
8a954faf54 target/arm: Add v8M stack checks for VLDM/VSTM
Add the v8M stack checks for the VLDM/VSTM
(aka VPUSH/VPOP) instructions. This code is currently
unreachable because we haven't yet implemented M profile
floating point support, but since the change is simple,
we add it now because otherwise we're likely to forget to
do it later.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20181002163556.10279-13-peter.maydell@linaro.org
2018-10-08 14:55:05 +01:00
Peter Maydell
aa369e5c08 target/arm: Add v8M stack checks for Thumb push/pop
Add v8M stack checks for the 16-bit Thumb push/pop
encodings: STMDB, STMFD, LDM, LDMIA, LDMFD.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20181002163556.10279-12-peter.maydell@linaro.org
2018-10-08 14:55:05 +01:00
Peter Maydell
0bc003bad9 target/arm: Add v8M stack checks for T32 load/store single
Add v8M stack checks for the instructions in the T32
"load/store single" encoding class: these are the
"immediate pre-indexed" and "immediate, post-indexed"
LDR and STR instructions.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20181002163556.10279-11-peter.maydell@linaro.org
2018-10-08 14:55:04 +01:00
Peter Maydell
7c0ed88e7d target/arm: Add v8M stack checks for Thumb2 LDM/STM
Add the v8M stack checks for:
 * LDM (T2 encoding)
 * STM (T2 encoding)

This includes the 32-bit encodings of the instructions listed
in v8M ARM ARM rule R_YVWT as
 * LDM, LDMIA, LDMFD
 * LDMDB, LDMEA
 * POP (multiple registers)
 * PUSH (muliple registers)
 * STM, STMIA, STMEA
 * STMDB, STMFD

We perform the stack limit before doing any other part
of the load or store.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20181002163556.10279-10-peter.maydell@linaro.org
2018-10-08 14:55:04 +01:00
Peter Maydell
910d7692e5 target/arm: Add v8M stack checks for LDRD/STRD (imm)
Add the v8M stack checks for:
 * LDRD (immediate)
 * STRD (immediate)

Loads and stores are more complicated than ADD/SUB/MOV, because we
must ensure that memory accesses below the stack limit are not
performed, so we can't simply do the check when we actually update
SP.

For these instructions, if the stack limit check triggers
we must not:
 * perform any memory access below the SP limit
 * update PC, SP or the load/store base register
but it is IMPDEF whether we:
 * perform any accesses above or equal to the SP limit
 * update destination registers for loads

For QEMU we choose to always check the limit before doing any other
part of the load or store, so we won't update any registers or
perform any memory accesses.

It is UNKNOWN whether the limit check triggers for a load or store
where the initial SP value is below the limit and one of the stores
would be below the limit, but the writeback moves SP to above the
limit.  For QEMU we choose to trigger the check in this situation.

Note that limit checks happen only for loads and stores which update
SP via writeback; they do not happen for loads and stores which
simply use SP as a base register.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20181002163556.10279-9-peter.maydell@linaro.org
2018-10-08 14:55:04 +01:00
Peter Maydell
a2d12f0f34 target/arm: Add some comments in Thumb decode
Add some comments to the Thumb decoder indicating what bits
of the instruction have been decoded at various points in
the code.

This is not an exhaustive set of comments; we're gradually
adding comments as we work with particular bits of the code.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20181002163556.10279-6-peter.maydell@linaro.org
2018-10-08 14:55:04 +01:00
Peter Maydell
5520318939 target/arm: Add v8M stack checks on ADD/SUB/MOV of SP
Add code to insert calls to a helper function to do the stack
limit checking when we handle these forms of instruction
that write to SP:
 * ADD (SP plus immediate)
 * ADD (SP plus register)
 * SUB (SP minus immediate)
 * SUB (SP minus register)
 * MOV (register)

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20181002163556.10279-5-peter.maydell@linaro.org
2018-10-08 14:55:04 +01:00
Peter Maydell
4730fb8503 target/arm: Define new TBFLAG for v8M stack checking
The Arm v8M architecture includes hardware stack limit checking.
When certain instructions update the stack pointer, if the new
value of SP is below the limit set in the associated limit register
then an exception is taken. Add a TB flag that tracks whether
the limit-checking code needs to be emitted.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20181002163556.10279-2-peter.maydell@linaro.org
2018-10-08 14:55:04 +01:00
Peter Maydell
d00584b7cf target/arm: Untabify translate.c
Untabify the arm translate.c. This affects only some lines,
mostly comments, in the iwMMXt code. We've never touched
that code in years, so it's not going to get fixed up
by our "change when touched" process, and a bulk change
is not going to be too disruptive.

This commit was produced using Emacs "untabify"; it is
a whitespace-only change.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 20180821165215.29069-2-peter.maydell@linaro.org
2018-08-24 13:17:47 +01:00
Peter Maydell
55c544ed27 target/arm: Implement AArch32 ERET instruction
ARMv7VE introduced the ERET instruction, which is necessary to
return from an exception taken to Hyp mode. Implement this.
In A32 encoding it is a completely new encoding; in T32 it
is an adjustment of the behaviour of the existing
"SUBS PC, LR, #<imm8>" instruction.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Reviewed-by: Luc Michel <luc.michel@greensocs.com>
Message-id: 20180814124254.5229-10-peter.maydell@linaro.org
2018-08-20 11:24:32 +01:00
Peter Maydell
aec4dd09f1 target/arm: Permit accesses to ELR_Hyp from Hyp mode via MSR/MRS (banked)
The MSR (banked) and MRS (banked) instructions allow accesses to ELR_Hyp
from either Monitor or Hyp mode. Our translate time check
was overly strict and only permitted access from Monitor mode.

The runtime check we do in msr_mrs_banked_exc_checks() had the
correct code in it, but never got there because of the earlier
"currmode == tgtmode" check. Special case ELR_Hyp.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Reviewed-by: Luc Michel <luc.michel@greensocs.com>
Message-id: 20180814124254.5229-9-peter.maydell@linaro.org
2018-08-20 11:24:32 +01:00
Roman Kapl
c2d9644e6d target/arm: Fix crash on conditional instruction in an IT block
If an instruction is conditional (like CBZ) and it is executed
conditionally (using the ITx instruction), a jump to an undefined
label is generated, and QEMU crashes.

CBZ in IT block is an UNPREDICTABLE behavior, but we should not
crash.  Honouring the condition code is allowed by the spec in this
case (constrained unpredictable, ARMv8, section K1.1.7), and matches
what we do for other "UNPREDICTABLE inside an IT block" instructions.

Fix the 'skip on condition' code to create a new label only if it
does not already exist.  Previously multiple labels were created, but
only the last one of them was set.

Signed-off-by: Roman Kapl <rka@sysgo.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20180816120533.6587-1-rka@sysgo.com
[PMM: fixed ^ 1 being applied to wrong argument, fixed typo]
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-08-20 11:24:31 +01:00
Richard Henderson
26c470a7bb target/arm: Implement ARMv8.2-DotProd
We've already added the helpers with an SVE patch, all that remains
is to wire up the aa64 and aa32 translators.  Enable the feature
within -cpu max for CONFIG_USER_ONLY.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20180627043328.11531-36-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-06-29 15:11:15 +01:00
Richard Henderson
2cc99919a8 target/arm: Pass index to AdvSIMD FCMLA (indexed)
For aa64 advsimd, we had been passing the pre-indexed vector.
However, sve applies the index to each 128-bit segment, so we
need to pass in the index separately.

For aa32 advsimd, the fp32 operation always has index 0, but
we failed to interpret the fp16 index correctly.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 20180627043328.11531-31-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-06-29 15:11:12 +01:00
Julia Suvorova
2aeba0d007 target/arm: Strict alignment for ARMv6-M and ARMv8-M Baseline
Unlike ARMv7-M, ARMv6-M and ARMv8-M Baseline only supports naturally
aligned memory accesses for load/store instructions.

Signed-off-by: Julia Suvorova <jusual@mail.ru>
Message-id: 20180622080138.17702-3-jusual@mail.ru
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-06-22 13:28:41 +01:00
Julia Suvorova
8297cb13e4 target/arm: Minor cleanup for ARMv6-M 32-bit instructions
The arrays were made static, "if" was simplified because V7M and V8M
define V6 feature.

Signed-off-by: Julia Suvorova <jusual@mail.ru>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20180618214604.6777-1-jusual@mail.ru
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-06-22 13:28:34 +01:00
Julia Suvorova
14120108f8 target/arm: Allow ARMv6-M Thumb2 instructions
ARMv6-M supports 6 Thumb2 instructions. This patch checks for these
instructions and allows their execution.
Like Thumb2 cores, ARMv6-M always interprets BL instruction as 32-bit.

This patch is required for future Cortex-M0 support.

Signed-off-by: Julia Suvorova <jusual@mail.ru>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20180612204632.28780-1-jusual@mail.ru
[PMM: move armv6m_insn[] and armv6m_mask[] closer to
 point of use, and mark 'const'. Check for M-and-not-v7
 rather than M-and-6.]
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-06-15 15:23:34 +01:00
Richard Henderson
07ea28b418 tcg: Pass tb and index to tcg_gen_exit_tb separately
Do the cast to uintptr_t within the helper, so that the compiler
can type check the pointer argument.  We can also do some more
sanity checking of the index argument.

Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2018-06-01 15:15:27 -07:00
Alex Bennée
486624fcd3 target/arm: convert conversion helpers to fpst/ahp_flag
Instead of passing env and leaving it up to the helper to get the
right fpstatus we pass it explicitly. There was already a get_fpstatus
helper for neon for the 32 bit code. We also add an get_ahp_flag() for
passing the state of the alternative FP16 format flag. This leaves
scope for later tracking the AHP state in translation flags.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2018-05-17 15:27:09 -07:00
Emilio G. Cota
b542683d77 translator: merge max_insns into DisasContextBase
While at it, use int for both num_insns and max_insns to make
sure we have same-type comparisons.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Michael Clark <mjc@sifive.com>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2018-05-09 10:12:21 -07:00
Emilio G. Cota
bfe7ad5be7 target/arm: avoid integer overflow in next_page PC check
If the PC is in the last page of the address space, next_page_start
overflows to 0. Fix it.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Cc: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2018-05-09 10:12:21 -07:00
Peter Maydell
b1e5336a98 target/arm: Implement v8M VLLDM and VLSTM
For v8M the instructions VLLDM and VLSTM support lazy saving
and restoring of the secure floating-point registers. Even
if the floating point extension is not implemented, these
instructions must act as NOPs in Secure state, so they can
be used as part of the secure-to-nonsecure call sequence.

Fixes: https://bugs.launchpad.net/qemu/+bug/1768295
Cc: qemu-stable@nongnu.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20180503105730.5958-1-peter.maydell@linaro.org
2018-05-04 18:05:51 +01:00
Aaron Lindsay
e69ad9df6c target/arm: Allow EL change hooks to do IO
During code generation, surround CPSR writes and exception returns which
call the EL change hooks with gen_io_start/end. The immediate need is
for the PMU to access the clock and icount during EL change to support
mode filtering.

Signed-off-by: Aaron Lindsay <alindsay@codeaurora.org>
Message-id: 1523997485-1905-9-git-send-email-alindsay@codeaurora.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-04-26 11:04:39 +01:00
Onur Sahin
c4869ca630 target-arm: Check undefined opcodes for SWP in A32 decoder
Make sure we are not treating architecturally Undefined instructions
as a SWP, by verifying the opcodes as per section A8.8.229 of ARMv7-A
specification. Bits [21:20] must be zero for this to be a SWP or SWPB.
We also choose to UNDEF for the architecturally UNPREDICTABLE case of
bits [11:8] not being zero.

Signed-off-by: Onur Sahin <onursahin08@gmail.com>
[PMM: tweaked commit message]
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-04-10 13:02:24 +01:00
Peter Maydell
c900a2e62d target/arm: Honour MDCR_EL2.TDE when routing exceptions due to BKPT/BRK
The MDCR_EL2.TDE bit allows the exception level targeted by debug
exceptions to be set to EL2 for code executing at EL0.  We handle
this in the arm_debug_target_el() function, but this is only used for
hardware breakpoint and watchpoint exceptions, not for the exception
generated when the guest executes an AArch32 BKPT or AArch64 BRK
instruction.  We don't have enough information for a translate-time
equivalent of arm_debug_target_el(), so instead make BKPT and BRK
call a special purpose helper which can do the routing, rather than
the generic exception_with_syndrome helper.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 20180320134114.30418-2-peter.maydell@linaro.org
2018-03-23 18:26:46 +00:00
Richard Henderson
0052087efb target/arm: Decode t32 simd 3reg and 2reg_scalar extension
Happily, the bits are in the same places compared to a32.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20180228193125.20577-16-richard.henderson@linaro.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-03-02 11:03:45 +00:00
Richard Henderson
638808ff8a target/arm: Decode aa32 armv8.3 2-reg-index
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20180228193125.20577-15-richard.henderson@linaro.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-03-02 11:03:45 +00:00
Richard Henderson
8b7209fae7 target/arm: Decode aa32 armv8.3 3-same
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 20180228193125.20577-14-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-03-02 11:03:45 +00:00
Richard Henderson
61adacc8f5 target/arm: Decode aa32 armv8.1 two reg and a scalar
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20180228193125.20577-9-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-03-02 11:03:45 +00:00
Richard Henderson
36a719348a target/arm: Decode aa32 armv8.1 three same
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20180228193125.20577-8-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-03-02 11:03:45 +00:00
Alex Bennée
9b04991686 target/arm/helper: pass explicit fpst to set_rmode
As the rounding mode is now split between FP16 and the rest of
floating point we need to be explicit when tweaking it. Instead of
passing the CPU env we now pass the appropriate fpst pointer directly.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20180227143852.11175-6-alex.bennee@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-03-01 11:13:59 +00:00
Peter Maydell
384c6c03fb target/arm/translate.c: Fix missing 'break' for TT insns
The code where we added the TT instruction was accidentally
missing a 'break', which meant that after generating the code
to execute the TT we would fall through to 'goto illegal_op'
and generate code to take an UNDEF insn.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 20180206103941.13985-1-peter.maydell@linaro.org
2018-02-09 10:55:39 +00:00
Richard Henderson
c39c2b9043 target/arm: Expand vector registers for SVE
Change vfp.regs as a uint64_t to vfp.zregs as an ARMVectorReg.
The previous patches have made the change in representation
relatively painless.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 20180123035349.24538-2-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-02-09 10:40:31 +00:00
Richard Henderson
9a2b5256ea target/arm: Add aa{32, 64}_vfp_{dreg, qreg} helpers
Helpers that return a pointer into env->vfp.regs so that we isolate
the logic of how to index the regs array for different cpu modes.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20180119045438.28582-7-richard.henderson@linaro.org
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-01-25 11:45:29 +00:00
Richard Henderson
3f68b8a5a6 target/arm: Change the type of vfp.regs
All direct users of this field want an integral value.  Drop all
of the extra casting between uint64_t and float64.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20180119045438.28582-6-richard.henderson@linaro.org
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-01-25 11:45:28 +00:00
Richard Henderson
e7c06c4e4c target/arm: Use pointers in neon tbl helper
Rather than passing a regno to the helper, pass pointers to the
vector register directly.  This eliminates the need to pass in
the environment pointer and reduces the number of places that
directly access env->vfp.regs[].

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20180119045438.28582-5-richard.henderson@linaro.org
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-01-25 11:45:28 +00:00
Richard Henderson
b13708bbbd target/arm: Use pointers in neon zip/uzp helpers
Rather than passing regnos to the helpers, pass pointers to the
vector registers directly.  This eliminates the need to pass in
the environment pointer and reduces the number of places that
directly access env->vfp.regs[].

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 20180119045438.28582-4-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-01-25 11:45:28 +00:00
Richard Henderson
1a66ac61af target/arm: Use pointers in crypto helpers
Rather than passing regnos to the helpers, pass pointers to the
vector registers directly.  This eliminates the need to pass in
the environment pointer and reduces the number of places that
directly access env->vfp.regs[].

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 20180119045438.28582-3-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-01-25 11:45:28 +00:00
Peter Maydell
2eea841c11 target/arm: Make disas_thumb2_insn() generate its own UNDEF exceptions
Refactor disas_thumb2_insn() so that it generates the code for raising
an UNDEF exception for invalid insns, rather than returning a flag
which the caller must check to see if it needs to generate the UNDEF
code. This brings the function in to line with the behaviour of
disas_thumb_insn() and disas_arm_insn().

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1513080506-17703-1-git-send-email-peter.maydell@linaro.org
2018-01-11 13:25:40 +00:00
Richard Henderson
15fa08f845 tcg: Dynamically allocate TCGOps
With no fixed array allocation, we can't overflow a buffer.
This will be important as optimizations related to host vectors
may expand the number of ops used.

Use QTAILQ to link the ops together.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2017-12-29 12:43:39 -08:00
Richard Henderson
f764718d0c tcg: Remove TCGV_UNUSED* and TCGV_IS_UNUSED*
These are now trivial sets and tests against NULL.  Unwrap.

Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2017-12-29 12:43:39 -08:00
Peter Maydell
5158de241b target/arm: Implement TT instruction
Implement the TT instruction which queries the security
state and access permissions of a memory location.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1512153879-5291-8-git-send-email-peter.maydell@linaro.org
2017-12-13 17:59:24 +00:00
Peter Maydell
62593718d7 target/arm: Split M profile MNegPri mmu index into user and priv
For M profile, we currently have an mmu index MNegPri for
"requested execution priority negative". This fails to
distinguish "requested execution priority negative, privileged"
from "requested execution priority negative, usermode", but
the two can return different results for MPU lookups. Fix this
by splitting MNegPri into MNegPriPriv and MNegPriUser, and
similarly for the Secure equivalent MSNegPri.

This takes us from 6 M profile MMU modes to 8, which means
we need to bump NB_MMU_MODES; this is OK since the point
where we are forced to reduce TLB sizes is 9 MMU modes.

(It would in theory be possible to stick with 6 MMU indexes:
{mpu-disabled,user,privileged} x {secure,nonsecure} since
in the MPU-disabled case the result of an MPU lookup is
always the same for both user and privileged code. However
we would then need to rework the TB flags handling to put
user/priv into the TB flags separately from the mmuidx.
Adding an extra couple of mmu indexes is simpler.)

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1512153879-5291-5-git-send-email-peter.maydell@linaro.org
2017-12-13 17:59:23 +00:00
Peter Maydell
7472e2efb0 target/arm: Generate UNDEF for 32-bit Thumb2 insns
The refactoring of commit 296e5a0a6c has a nasty bug:
it accidentally dropped the generation of code to raise
the UNDEF exception when disas_thumb2_insn() returns nonzero.
This means that 32-bit Thumb2 instruction patterns that
ought to UNDEF just act like nops instead. This is likely
to break any number of things, including the kernel's "disable
the FPU and use the UNDEF exception to identify when to turn
it back on again" trick.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1513006964-3371-1-git-send-email-peter.maydell@linaro.org
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2017-12-11 17:11:27 +00:00
Peter Maydell
3448d47b31 translate.c: Fix usermode big-endian AArch32 LDREXD and STREXD
For AArch32 LDREXD and STREXD, architecturally the 32-bit word at the
lowest address is always Rt and the one at addr+4 is Rt2, even if the
CPU is big-endian. Our implementation does these with a single
64-bit store, so if we're big-endian then we need to put the two
32-bit halves together in the opposite order to little-endian,
so that they end up in the right places. We were trying to do
this with the gen_aa32_frob64() function, but that is not correct
for the usermode emulator, because there there is a distinction
between "load a 64 bit value" (which does a BE 64-bit access
and doesn't need swapping) and "load two 32 bit values as one
64 bit access" (where we still need to do the swapping, like
system mode BE32).

Fixes: https://bugs.launchpad.net/qemu/+bug/1725267
Cc: qemu-stable@nongnu.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1509622400-13351-1-git-send-email-peter.maydell@linaro.org
2017-11-07 13:03:51 +00:00
Stefano Stabellini
58803318e5 fix WFI/WFE length in syndrome register
WFI/E are often, but not always, 4 bytes long. When they are, we need to
set ARM_EL_IL_SHIFT in the syndrome register.

Pass the instruction length to HELPER(wfi), use it to decrement pc
appropriately and to pass an is_16bit flag to syn_wfx, which sets
ARM_EL_IL_SHIFT if needed.

Set dc->insn in both arm_tr_translate_insn and thumb_tr_translate_insn.

Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
Message-id: alpine.DEB.2.10.1710241055160.574@sstabellini-ThinkPad-X260
[PMM: move setting of dc->insn for Thumb so it is correct for 32 bit insns]
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2017-10-31 11:50:50 +00:00
Peter Maydell
6e6430a821 Capstone disassembler
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Merge remote-tracking branch 'remotes/rth/tags/pull-dis-20171026' into staging

Capstone disassembler

# gpg: Signature made Thu 26 Oct 2017 10:57:27 BST
# gpg:                using RSA key 0x64DF38E8AF7E215F
# gpg: Good signature from "Richard Henderson <richard.henderson@linaro.org>"
# Primary key fingerprint: 7A48 1E78 868B 4DB6 A85A  05C0 64DF 38E8 AF7E 215F

* remotes/rth/tags/pull-dis-20171026:
  disas: Add capstone as submodule
  disas: Remove monitor_disas_is_physical
  ppc: Support Capstone in disas_set_info
  arm: Support Capstone in disas_set_info
  i386: Support Capstone in disas_set_info
  disas: Support the Capstone disassembler library
  disas: Remove unused flags arguments
  target/arm: Don't set INSN_ARM_BE32 for CONFIG_USER_ONLY
  target/arm: Move BE32 disassembler fixup
  target/ppc: Convert to disas_set_info hook
  target/i386: Convert to disas_set_info hook

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

# Conflicts:
#	target/i386/cpu.c
#	target/ppc/translate_init.c
2017-10-27 08:04:51 +01:00
Richard Henderson
1d48474d8e disas: Remove unused flags arguments
Now that every target is using the disas_set_info hook,
the flags argument is unused.  Remove it.

Tested-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2017-10-25 11:55:09 +02:00
Richard Henderson
1c2adb958f tcg: Initialize cpu_env generically
This is identical for each target.  So, move the initialization to
common code.  Move the variable itself out of tcg_ctx and name it
cpu_env to minimize changes within targets.

This also means we can remove tcg_global_reg_new_{ptr,i32,i64},
since there are no longer global-register temps created by targets.

Reviewed-by: Emilio G. Cota <cota@braap.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2017-10-24 13:53:42 -07:00
Emilio G. Cota
b1311c4acf tcg: define tcg_init_ctx and make tcg_ctx a pointer
Groundwork for supporting multiple TCG contexts.

The core of this patch is this change to tcg/tcg.h:

> -extern TCGContext tcg_ctx;
> +extern TCGContext tcg_init_ctx;
> +extern TCGContext *tcg_ctx;

Note that for now we set *tcg_ctx to whatever TCGContext is passed
to tcg_context_init -- in this case &tcg_init_ctx.

Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2017-10-24 13:53:42 -07:00
Emilio G. Cota
2399d4e7ce target/arm: check CF_PARALLEL instead of parallel_cpus
Thereby decoupling the resulting translated code from the current state
of the system.

Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2017-10-24 13:53:41 -07:00
Emilio G. Cota
c5a49c63fa tcg: convert tb->cflags reads to tb_cflags(tb)
Convert all existing readers of tb->cflags to tb_cflags, so that we
use atomic_read and therefore avoid undefined behaviour in C11.

Note that the remaining setters/getters of the field are protected
by tb_lock, and therefore do not need conversion.

Luckily all readers access the field via 'tb->cflags' (so no foo.cflags,
bar->cflags in the code base), which makes the conversion easily
scriptable:

FILES=$(git grep 'tb->cflags' target include/exec/gen-icount.h \
	 accel/tcg/translator.c | cut -f1 -d':' | sort | uniq)

perl -pi -e 's/([^.>])tb->cflags/$1tb_cflags(tb)/g' $FILES
perl -pi -e 's/([a-z->.]*)(->|\.)tb->cflags/tb_cflags($1$2tb)/g' $FILES

Then manually fixed the few errors that checkpatch reported.

Compile-tested for all targets.

Suggested-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2017-10-24 13:53:41 -07:00
Peter Maydell
76eff04d16 target/arm: Implement SG instruction corner cases
The common situation of the SG instruction is that it is
executed from S&NSC memory by a CPU in NS state. That case
is handled by v7m_handle_execute_nsc(). However the instruction
also has defined behaviour in a couple of other cases:
 * SG instruction in NS memory (behaves as a NOP)
 * SG in S memory but CPU already secure (clears IT bits and
   does nothing else)
 * SG instruction in v8M without Security Extension (NOP)

These can be implemented in translate.c.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1507556919-24992-10-git-send-email-peter.maydell@linaro.org
2017-10-12 13:23:14 +01:00
Peter Maydell
dcf14dfb70 target/arm: Support some Thumb insns being always unconditional
A few Thumb instructions are always unconditional even inside an
IT block (as opposed to being UNPREDICTABLE if used inside an
IT block): BKPT, the v8M SG instruction, and the A profile
HLT (debug halt) instruction.

This means we need to suppress the jump-over-instruction-on-condfail
code generation (though the IT state still advances as usual and
subsequent insns in the IT block may be conditional).

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1507556919-24992-9-git-send-email-peter.maydell@linaro.org
2017-10-12 13:23:14 +01:00
Peter Maydell
5b8d7289e9 target-arm: Simplify insn_crosses_page()
Recent changes have left insn_crosses_page() more complicated
than it needed to be:
 * it's only called from thumb_tr_translate_insn() so we know
   for certain that we're looking at a Thumb insn
 * the caller's check for dc->pc >= dc->next_page_start - 3
   means that dc->pc can't possibly be 4 aligned, so there's
   no need to check that (the check was partly there to ensure
   that we didn't treat an ARM insn as Thumb, I think)
 * we now have thumb_insn_is_16bit() which lets us do a precise
   check of the length of the next insn, rather than opencoding
   an inaccurate check

Simplify it down to just loading the first half of the insn
and calling thumb_insn_is_16bit() on it.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1507556919-24992-8-git-send-email-peter.maydell@linaro.org
2017-10-12 13:23:14 +01:00
Peter Maydell
296e5a0a6c target/arm: Pull Thumb insn word loads up to top level
Refactor the Thumb decode to do the loads of the instruction words at
the top level rather than only loading the second half of a 32-bit
Thumb insn in the middle of the decode.

This is simple apart from the awkward case of Thumb1, where the
BL/BLX prefix and suffix instructions live in what in Thumb2 is the
32-bit insn space.  To handle these we decode enough to identify
whether we're looking at a prefix/suffix that we handle as a 16 bit
insn, or a prefix that we're going to merge with the following suffix
to consider as a 32 bit insn.  The translation of the 16 bit cases
then moves from disas_thumb2_insn() to disas_thumb_insn().

The refactoring has the benefit that we don't need to pass the
CPUARMState* down into the decoder code any more, but the major
reason for doing this is that some Thumb instructions must be always
unconditional regardless of the IT state bits, so we need to know the
whole insn before we emit the "skip this insn if the IT bits and cond
state tell us to" code.  (The always unconditional insns are BKPT,
HLT and SG; the last of these is 32 bits.)

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1507556919-24992-7-git-send-email-peter.maydell@linaro.org
2017-10-12 13:23:14 +01:00
Peter Maydell
6b8acf256d target-arm: Don't check for "Thumb2 or M profile" for not-Thumb1
The code which implements the Thumb1 split BL/BLX instructions
is guarded by a check on "not M or THUMB2". All we really need
to check here is "not THUMB2" (and we assume that elsewhere too,
eg in the ARCH(6T2) test that UNDEFs the Thumb2 insns).

This doesn't change behaviour because all M profile cores
have Thumb2 and so ARM_FEATURE_M implies ARM_FEATURE_THUMB2.
(v6M implements a very restricted subset of Thumb2, but we
can cross that bridge when we get to it with appropriate
feature bits.)

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1507556919-24992-6-git-send-email-peter.maydell@linaro.org
2017-10-12 13:23:14 +01:00
Peter Maydell
d02a8698d7 target/arm: Implement secure function return
Secure function return happens when a non-secure function has been
called using BLXNS and so has a particular magic LR value (either
0xfefffffe or 0xfeffffff). The function return via BX behaves
specially when the new PC value is this magic value, in the same
way that exception returns are handled.

Adjust our BX excret guards so that they recognize the function
return magic number as well, and perform the function-return
unstacking in do_v7m_exception_exit().

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Acked-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1507556919-24992-5-git-send-email-peter.maydell@linaro.org
2017-10-12 13:23:14 +01:00
Peter Maydell
3e3fa230e3 target/arm: Implement BLXNS
Implement the BLXNS instruction, which allows secure code to
call non-secure code.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1507556919-24992-4-git-send-email-peter.maydell@linaro.org
2017-10-12 13:23:14 +01:00
Peter Maydell
b9f587d62c target/arm: Add M profile secure MMU index values to get_a32_user_mem_index()
Add the M profile secure MMU index values to the switch in
get_a32_user_mem_index() so that LDRT/STRT work correctly
rather than asserting at translate time.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1507556919-24992-2-git-send-email-peter.maydell@linaro.org
2017-10-12 13:23:14 +01:00
Emilio G. Cota
7f11636dbe tcg: remove addr argument from lookup_tb_ptr
It is unlikely that we will ever want to call this helper passing
an argument other than the current PC. So just remove the argument,
and use the pc we already get from cpu_get_tb_cpu_state.

This change paves the way to having a common "tb_lookup" function.

Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2017-10-10 07:37:10 -07:00
Peter Maydell
ef475b5dd1 target-arm:
* cleanups converting to DEFINE_PROP_LINK
  * allwinner-a10: mark as not user-creatable
  * initial patches working towards ARMv8M support
  * implement generating aborts on memory transaction failures
  * make BXJ behave correctly (ie not UNDEF) on ARMv6-and-later
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Merge remote-tracking branch 'remotes/pmaydell/tags/pull-target-arm-20170907' into staging

target-arm:
 * cleanups converting to DEFINE_PROP_LINK
 * allwinner-a10: mark as not user-creatable
 * initial patches working towards ARMv8M support
 * implement generating aborts on memory transaction failures
 * make BXJ behave correctly (ie not UNDEF) on ARMv6-and-later

# gpg: Signature made Thu 07 Sep 2017 14:26:07 BST
# gpg:                using RSA key 0x3C2525ED14360CDE
# gpg: Good signature from "Peter Maydell <peter.maydell@linaro.org>"
# gpg:                 aka "Peter Maydell <pmaydell@gmail.com>"
# gpg:                 aka "Peter Maydell <pmaydell@chiark.greenend.org.uk>"
# Primary key fingerprint: E1A5 C593 CD41 9DE2 8E83  15CF 3C25 25ED 1436 0CDE

* remotes/pmaydell/tags/pull-target-arm-20170907: (31 commits)
  target/arm: Add Jazelle feature
  target/arm: Implement new do_transaction_failed hook
  hw/arm: Set ignore_memory_transaction_failures for most ARM boards
  boards.h: Define new flag ignore_memory_transaction_failures
  target/arm: Implement BXNS, and banked stack pointers
  target/arm: Move regime_is_secure() to target/arm/internals.h
  target/arm: Make CFSR register banked for v8M
  target/arm: Make MMFAR banked for v8M
  target/arm: Make CCR register banked for v8M
  target/arm: Make MPU_CTRL register banked for v8M
  target/arm: Make MPU_RNR register banked for v8M
  target/arm: Make MPU_RBAR, MPU_RLAR banked for v8M
  target/arm: Make MPU_MAIR0, MPU_MAIR1 registers banked for v8M
  target/arm: Make VTOR register banked for v8M
  nvic: Add NS alias SCS region
  target/arm: Make CONTROL register banked for v8M
  target/arm: Make FAULTMASK register banked for v8M
  target/arm: Make PRIMASK register banked for v8M
  target/arm: Make BASEPRI register banked for v8M
  target/arm: Add MMU indexes for secure v8M
  ...

# Conflicts:
#	target/arm/translate.c
2017-09-07 16:46:15 +01:00
Portia Stephens
c99a55d38d target/arm: Add Jazelle feature
This adds a feature bit indicating support of the (trivial) Jazelle
implementation if ARM_FEATURE_V6 is set or if the processor is arm926
or arm1026.  This fixes the issue that any BXJ instruction will
result in an illegal_op.  BXJ instructions will now check if the
architecture supports ARM_FEATURE_JAZELLE.

Signed-off-by: Portia Stephens <portia.stephens@xilinx.com>
Reviewed-by: Alistair Francis <alistair.francis@xilinx.com>
Message-id: 20170905211232.11092-1-portia.stephens@xilinx.com
[PMM: edited commit message and comment text a bit]
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2017-09-07 13:54:55 +01:00
Peter Maydell
fb602cb726 target/arm: Implement BXNS, and banked stack pointers
Implement the BXNS v8M instruction, which is like BX but will do a
jump-and-switch-to-NonSecure if the branch target address has bit 0
clear.

This is the first piece of code which implements "switch to the
other security state", so the commit also includes the code to
switch the stack pointers around, which is the only complicated
part of switching security state.

BLXNS is more complicated than just "BXNS but set the link register",
so we leave it for a separate commit.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1503414539-28762-21-git-send-email-peter.maydell@linaro.org
2017-09-07 13:54:54 +01:00
Peter Maydell
8bfc26ea30 target/arm: Make CONTROL register banked for v8M
Make the CONTROL register banked if v8M security extensions are enabled.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1503414539-28762-10-git-send-email-peter.maydell@linaro.org
2017-09-07 13:54:53 +01:00
Peter Maydell
1e577cc7cf target/arm: Add state field, feature bit and migration for v8M secure state
As the first step in implementing ARM v8M's security extension:
 * add a new feature bit ARM_FEATURE_M_SECURITY
 * add the CPU state field that indicates whether the CPU is
   currently in the secure state
 * add a migration subsection for this new state
   (we will add the Secure copies of banked register state
   to this subsection in later patches)
 * add a #define for the one new-in-v8M exception type
 * make the CPU debug log print S/NS status

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1503414539-28762-4-git-send-email-peter.maydell@linaro.org
2017-09-07 13:54:52 +01:00
Richard Henderson
d0264d86b0 target/arm: Perform per-insn cross-page check only for Thumb
ARM is a fixed-length ISA and we can compute the page crossing
condition exactly once during init_disas_context.

Reviewed-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-06 08:06:48 -07:00
Richard Henderson
722ef0a562 target/arm: Split out thumb_tr_translate_insn
We need not check for ARM vs Thumb state in order to dispatch
disassembly of every instruction.

Tested-by: Emilio G. Cota <cota@braap.org>
Reviewed-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-06 08:06:48 -07:00
Richard Henderson
f7708456aa target/arm: Move ss check to init_disas_context
We can check for single-step just once.

Reviewed-by: Emilio G. Cota <cota@braap.org>
Reviewed-by: Lluís Vilanova <vilanova@ac.upc.edu>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-06 08:06:48 -07:00
Lluís Vilanova
2316922420 target/arm: [tcg] Port to generic translation framework
Tested-by: Emilio G. Cota <cota@braap.org>
Reviewed-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Message-Id: <150002631325.22386.10348327185029496649.stgit@frigg.lan>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-06 08:06:48 -07:00
Lluís Vilanova
4013f7fc81 target/arm: [tcg] Port to disas_log
Incrementally paves the way towards using the generic instruction translation
loop.

Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Alex Benneé <alex.benee@linaro.org>
Message-Id: <150002582711.22386.191527630537864599.stgit@frigg.lan>
[rth: Move tb->size computation and use that result.]
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-06 08:06:48 -07:00
Lluís Vilanova
70d3c035ae target/arm: [tcg] Port to tb_stop
Incrementally paves the way towards using the generic instruction translation
loop.

Reviewed-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Message-Id: <150002534291.22386.13499916738708680298.stgit@frigg.lan>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-06 08:06:48 -07:00
Lluís Vilanova
13189a9080 target/arm: [tcg] Port to translate_insn
Incrementally paves the way towards using the generic instruction translation
loop.

Reviewed-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Message-Id: <150002485863.22386.13949856269576226529.stgit@frigg.lan>
[rth: Adjust for translate_insn interface change.]
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-06 08:06:47 -07:00
Lluís Vilanova
a68956ad7f target/arm: [tcg,a64] Port to insn_start
Incrementally paves the way towards using the generic instruction translation
loop.

Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Alex Benneé <alex.benee@linaro.org>
Message-Id: <150002413187.22386.156315485813606121.stgit@frigg.lan>
[rth: Use DISAS_TOO_MANY for "execute only one more" after bp.]
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-06 08:06:47 -07:00
Lluís Vilanova
f62bd897e6 target/arm: [tcg] Port to insn_start
Incrementally paves the way towards using the generic instruction translation
loop.

Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Alex Benneé <alex.benee@linaro.org>
Message-Id: <150002388959.22386.12439646324427589940.stgit@frigg.lan>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-06 08:06:47 -07:00
Lluís Vilanova
b14768544f target/arm: [tcg] Port to tb_start
Incrementally paves the way towards using the generic instruction translation
loop.

Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Alex Benneé <alex.benee@linaro.org>
Message-Id: <150002364681.22386.1701754996184325808.stgit@frigg.lan>
[rth: Adjust for tb_start interface change.]
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-06 08:06:47 -07:00
Lluís Vilanova
1d8a553523 target/arm: [tcg] Port to init_disas_context
Incrementally paves the way towards using the generic instruction translation
loop.

Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Alex Benneé <alex.benee@linaro.org>
Message-Id: <150002316201.22386.12115078843605656029.stgit@frigg.lan>
[rth: Adjust for max_insns interface change.]
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-06 08:06:47 -07:00
Lluís Vilanova
dcba3a8d44 target/arm: [tcg] Port to DisasContextBase
Incrementally paves the way towards using the generic
instruction translation loop.

Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Alex Benneé <alex.benee@linaro.org>
Message-Id: <150002291931.22386.11441154993010495674.stgit@frigg.lan>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-06 08:06:47 -07:00
Richard Henderson
3805c2eba8 target/arm: Delay check for magic kernel page
There's nothing magic about the exception that we generate in order
to execute the magic kernel page.  We can and should allow gdb to
set a breakpoint at this location.

Reviewed-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-06 08:06:47 -07:00
Lluís Vilanova
77fc6f5e28 target: [tcg] Use a generic enum for DISAS_ values
Used later. An enum makes expected values explicit and
bounds the value space of switches.

Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Reviewed-by: Emilio G. Cota <cota@braap.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Message-Id: <150002049746.22386.2316077281615710615.stgit@frigg.lan>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-06 08:06:47 -07:00
Richard Henderson
a0c231e651 target/arm: Use DISAS_NORETURN
Fold DISAS_EXC and DISAS_TB_JUMP into DISAS_NORETURN.

In both cases all following code is dead.  In the first
case because we have exited the TB via exception; in the
second case because we have exited the TB via goto_tb
and its associated machinery.

Reviewed-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-06 08:06:47 -07:00
Peter Maydell
5b906f3589 target/arm: Make arm_cpu_dump_state() handle the M-profile XPSR
Make the arm_cpu_dump_state() debug logging handle the M-profile XPSR
rather than assuming it's an A-profile CPSR.  On M profile the PSR
line of a register dump will now look like this:

XPSR=41000000 -Z-- T priv-thread

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1501692241-23310-12-git-send-email-peter.maydell@linaro.org
2017-09-04 15:21:52 +01:00
Peter Maydell
ebfe27c593 target/arm: Tighten up Thumb decode where new v8M insns will be
Tighten up the T32 decoder in the places where new v8M instructions
will be:
 * TT/TTT/TTA/TTAT are in what was nominally LDREX/STREX r15, ...
   which is UNPREDICTABLE:
   make the UNPREDICTABLE behaviour be to UNDEF
 * BXNS/BLXNS are distinguished from BX/BLX via the low 3 bits,
   which in previous architectural versions are SBZ:
   enforce the SBZ via UNDEF rather than ignoring it, and move
   the "ARCH(5)" UNDEF case up so we don't leak a TCG temporary
 * SG is in the encoding which would be LDRD/STRD with rn = r15;
   this is UNPREDICTABLE and we currently UNDEF:
   move this check further up the code so that we don't leak
   TCG temporaries in the UNDEF case and have a better place
   to put the SG decode.

This means that if a v8M binary is accidentally run on v7M
or if a test case hits something that we haven't implemented
yet the behaviour will be obvious (UNDEF) rather than obscure
(plough on treating it as a different instruction).

In the process, add some comments about the instruction patterns
at these points in the decode. Our Thumb and ARM decoders are
very difficult to understand currently, but gradually adding
comments like this should help to clarify what exactly has
been decoded when.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1501692241-23310-5-git-send-email-peter.maydell@linaro.org
2017-09-04 15:21:51 +01:00
Lluís Vilanova
9c489ea6be tcg: Pass generic CPUState to gen_intermediate_code()
Needed to implement a target-agnostic gen_intermediate_code()
in the future.

Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Alex Benneé <alex.benee@linaro.org>
Reviewed-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Message-Id: <150002025498.22386.18051908483085660588.stgit@frigg.lan>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-07-19 14:45:16 -07:00
Aurelien Jarno
68cedf733a target/arm: optimize aarch32 rev16
Use the same mask to avoid having to load two different constants, as
suggested by Richard Henderson.

Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Message-Id: <20170516230159.4195-2-aurelien@aurel32.net>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-07-19 14:45:15 -07:00
Alex Bennée
b29fd33db5 target/arm: use DISAS_EXIT for eret handling
Previously DISAS_JUMP did ensure this but with the optimisation of
8a6b28c7 (optimize indirect branches) we might not leave the loop.
This means if any pending interrupts are cleared by changing IRQ flags
we might never get around to servicing them. You usually notice this
by seeing the lookup_tb_ptr() helper gainfully chaining TBs together
while cpu->interrupt_request remains high and the exit_request has not
been set.

This breaks amongst other things the OPTEE test suite which executes
an eret from the secure world after a non-secure world IRQ has gone
pending which then never gets serviced.

Instead of using the previously implied semantics of DISAS_JUMP we use
DISAS_EXIT which will always exit the run-loop.

CC: Etienne Carriere <etienne.carriere@linaro.org>
CC: Joakim Bech <joakim.bech@linaro.org>
CC: Jaroslaw Pelczar <j.pelczar@samsung.com>
CC: Peter Maydell <peter.maydell@linaro.org>
CC: Emilio G. Cota <cota@braap.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Message-id: 20170713141928.25419-7-alex.bennee@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2017-07-17 13:36:07 +01:00
Alex Bennée
0b609cc128 target/arm: use gen_goto_tb for ISB handling
While an ISB will ensure any raised IRQs happen on the next
instruction it doesn't cause any to get raised by itself. We can
therefore use a simple tb exit for ISB instructions and rely on the
exit_request check at the top of each TB to deal with exiting if
needed.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Message-id: 20170713141928.25419-6-alex.bennee@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2017-07-17 13:36:07 +01:00
Alex Bennée
4cae8f56fb target/arm/translate: ensure gen_goto_tb sets exit flags
As the gen_goto_tb function can do both static and dynamic jumps it
should also set the is_jmp field. This matches the behaviour of the
a64 code.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Message-id: 20170713141928.25419-5-alex.bennee@linaro.org
[tweak to multiline comment formatting]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2017-07-17 13:36:07 +01:00
Alex Bennée
e8d5230221 target/arm/translate: make DISAS_UPDATE match declared semantics
DISAS_UPDATE should be used when the wider CPU state other than just
the PC has been updated and we should therefore exit the TCG runtime
and return to the main execution loop rather assuming DISAS_JUMP would
do that.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Message-id: 20170713141928.25419-3-alex.bennee@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2017-07-17 13:36:07 +01:00
Emilio G. Cota
8a6b28c7b5 target/arm: optimize indirect branches
Speed up indirect branches by jumping to the target if it is valid.

Softmmu measurements (see later commit for user-mode results):

Note: baseline (i.e. speedup == 1x) is QEMU v2.9.0.

- Impact on Boot time

| setup  | ARM debian jessie boot+shutdown time | stddev |
|--------+--------------------------------------+--------|
| v2.9.0 |                                 8.84 |   0.07 |
| +cross |                                 8.85 |   0.03 |
| +jr    |                                 8.83 |   0.06 |

-                            NBench, arm-softmmu (debian jessie guest). Host: Intel i7-4790K @ 4.00GHz

  1.3x +-+-------------------------------------------------------------------------------------------------------------+-+
       |                                                                                                                 |
       |   cross                                                          ####                                           |
 1.25x +cross+jr..........................................................#++#.........................................+-+
       |                                                        ####      #  #                                           |
       |                                                     +++#  #      #  #                                           |
       |                                      +++            ****  #      #  #                                           |
  1.2x +-+...................................####............*..*..#......#..#.........................................+-+
       |                                  ****  #            *  *  #      #  #     ####                                  |
       |                                  *  *  #            *  *  #      #  #     #  #                                  |
 1.15x +-+................................*..*..#............*..*..#......#..#.....#..#................................+-+
       |                                  *  *  #            *  *  #      #  #     #  #                                  |
       |                                  *  *  #      ####  *  *  #      #  #     #  #                                  |
       |                                  *  *  #      #  #  *  *  #      #  #     #  #                         ####     |
  1.1x +-+................................*..*..#......#..#..*..*..#......#..#.....#..#.........................#..#...+-+
       |                                  *  *  #      #  #  *  *  #      #  #     #  #                         #  #     |
       |                                  *  *  #      #  #  *  *  #      #  #     #  #                         #  #     |
 1.05x +-+..........................####..*..*..#......#..#..*..*..#......#..#.....#..#......+++............*****..#...+-+
       |                        *****  #  *  *  #      #  #  *  *  #  *****  #     #  #   +++ |    ****###  *   *  #     |
       |                        *+++*  #  *  *  #      #  #  *  *  #  *+++*  #  ****  #  *****###  *  *  #  *   *  #     |
       |     *****###  +++####  *   *  #  *  *  #  *****  #  *  *  #  *   *  #  *  *  #  * | *++#  *  *  #  *   *  #     |
    1x +-++-+*+++*-+#++****++#++*+-+*++#+-*++*++#-+*+++*-+#++*++*++#++*+-+*++#+-*++*++#-+*+++*-+#++*++*++#++*+-+*++#+-++-+
       |     *   *  #  *  *  #  *   *  #  *  *  #  *   *  #  *  *  #  *   *  #  *  *  #  *   *  #  *  *  #  *   *  #     |
       |     *   *  #  *  *  #  *   *  #  *  *  #  *   *  #  *  *  #  *   *  #  *  *  #  *   *  #  *  *  #  *   *  #     |
 0.95x +-+---*****###--****###--*****###--****###--*****###--****###--*****###--****###--*****###--****###--*****###---+-+
       ASSIGNMENT BITFIELD   FOURFP EMULATION   HUFFMAN   LU DECOMPOSITIONEURAL NNUMERIC SOSTRING SORT     hmean
  png: http://imgur.com/eOLmZNR

NB. 'cross' represents the previous commit.

Signed-off-by: Emilio G. Cota <cota@braap.org>
Message-Id: <1493263764-18657-8-git-send-email-cota@braap.org>
[rth: Replace gen_jr global variable with DISAS_EXIT state.]
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-06-05 09:25:42 -07:00
Emilio G. Cota
7ad55b4ffd target/arm: optimize cross-page direct jumps in softmmu
Instead of unconditionally exiting to the exec loop, use the
lookup_and_goto_ptr helper to jump to the target if it is valid.

Perf impact: see next commit's log.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Message-Id: <1493263764-18657-7-git-send-email-cota@braap.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-06-05 09:25:42 -07:00
Peter Maydell
3bef701256 arm: Implement HFNMIENA support for M profile MPU
Implement HFNMIENA support for the M profile MPU. This bit controls
whether the MPU is treated as enabled when executing at execution
priorities of less than zero (in NMI, HardFault or with the FAULTMASK
bit set).

Doing this requires us to use a different MMU index for "running
at execution priority < 0", because we will have different
access permissions for that case versus the normal case.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1493122030-32191-14-git-send-email-peter.maydell@linaro.org
2017-06-02 11:51:49 +01:00
Peter Maydell
e7b921c2d9 arm: Use different ARMMMUIdx values for M profile
Make M profile use completely separate ARMMMUIdx values from
those that A profile CPUs use. This is a prelude to adding
support for the MPU and for v8M, which together will require
6 MMU indexes which don't map cleanly onto the A profile
uses:
 non secure User
 non secure Privileged
 non secure Privileged, execution priority < 0
 secure User
 secure Privileged
 secure Privileged, execution priority < 0

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1493122030-32191-4-git-send-email-peter.maydell@linaro.org
2017-06-02 11:51:47 +01:00
Peter Maydell
8bd5c82030 arm: Add support for M profile CPUs having different MMU index semantics
The M profile CPU's MPU has an awkward corner case which we
would like to implement with a different MMU index.

We can avoid having to bump the number of MMU modes ARM
uses, because some of our existing MMU indexes are only
used by non-M-profile CPUs, so we can borrow one.
To avoid that getting too confusing, clean up the code
to try to keep the two meanings of the index separate.

Instead of ARMMMUIdx enum values being identical to core QEMU
MMU index values, they are now the core index values with some
high bits set. Any particular CPU always uses the same high
bits (so eventually A profile cores and M profile cores will
use different bits). New functions arm_to_core_mmu_idx()
and core_to_arm_mmu_idx() convert between the two.

In general core index values are stored in 'int' types, and
ARM values are stored in ARMMMUIdx types.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1493122030-32191-3-git-send-email-peter.maydell@linaro.org
2017-06-02 11:51:47 +01:00
Peter Maydell
f4e8e4edda arm: Remove workarounds for old M-profile exception return implementation
Now that we've rewritten M-profile exception return so that the magic
PC values are not visible to other parts of QEMU, we can delete the
special casing of them elsewhere.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Message-id: 1491844419-12485-10-git-send-email-peter.maydell@linaro.org
2017-04-20 17:39:17 +01:00
Peter Maydell
3bb8a96f53 arm: Implement M profile exception return properly
On M profile, return from exceptions happen when code in Handler mode
executes one of the following function call return instructions:
 * POP or LDM which loads the PC
 * LDR to PC
 * BX register
and the new PC value is 0xFFxxxxxx.

QEMU tries to implement this by not treating the instruction
specially but then catching the attempt to execute from the magic
address value.  This is not ideal, because:
 * there are guest visible differences from the architecturally
   specified behaviour (for instance jumping to 0xFFxxxxxx via a
   different instruction should not cause an exception return but it
   will in the QEMU implementation)
 * we have to account for it in various places (like refusing to take
   an interrupt if the PC is at a magic value, and making sure that
   the MPU doesn't deny execution at the magic value addresses)

Drop these hacks, and instead implement exception return the way the
architecture specifies -- by having the relevant instructions check
for the magic value and raise the 'do an exception return' QEMU
internal exception immediately.

The effect on the generated code is minor:

 bx lr, old code (and new code for Thread mode):
  TCG:
   mov_i32 tmp5,r14
   movi_i32 tmp6,$0xfffffffffffffffe
   and_i32 pc,tmp5,tmp6
   movi_i32 tmp6,$0x1
   and_i32 tmp5,tmp5,tmp6
   st_i32 tmp5,env,$0x218
   exit_tb $0x0
   set_label $L0
   exit_tb $0x7f2aabd61993
  x86_64 generated code:
   0x7f2aabe87019:  mov    %ebx,%ebp
   0x7f2aabe8701b:  and    $0xfffffffffffffffe,%ebp
   0x7f2aabe8701e:  mov    %ebp,0x3c(%r14)
   0x7f2aabe87022:  and    $0x1,%ebx
   0x7f2aabe87025:  mov    %ebx,0x218(%r14)
   0x7f2aabe8702c:  xor    %eax,%eax
   0x7f2aabe8702e:  jmpq   0x7f2aabe7c016

 bx lr, new code when in Handler mode:
  TCG:
   mov_i32 tmp5,r14
   movi_i32 tmp6,$0xfffffffffffffffe
   and_i32 pc,tmp5,tmp6
   movi_i32 tmp6,$0x1
   and_i32 tmp5,tmp5,tmp6
   st_i32 tmp5,env,$0x218
   movi_i32 tmp5,$0xffffffffff000000
   brcond_i32 pc,tmp5,geu,$L1
   exit_tb $0x0
   set_label $L1
   movi_i32 tmp5,$0x8
   call exception_internal,$0x0,$0,env,tmp5
  x86_64 generated code:
   0x7fe8fa1264e3:  mov    %ebp,%ebx
   0x7fe8fa1264e5:  and    $0xfffffffffffffffe,%ebx
   0x7fe8fa1264e8:  mov    %ebx,0x3c(%r14)
   0x7fe8fa1264ec:  and    $0x1,%ebp
   0x7fe8fa1264ef:  mov    %ebp,0x218(%r14)
   0x7fe8fa1264f6:  cmp    $0xff000000,%ebx
   0x7fe8fa1264fc:  jae    0x7fe8fa126509
   0x7fe8fa126502:  xor    %eax,%eax
   0x7fe8fa126504:  jmpq   0x7fe8fa122016
   0x7fe8fa126509:  mov    %r14,%rdi
   0x7fe8fa12650c:  mov    $0x8,%esi
   0x7fe8fa126511:  mov    $0x56095dbeccf5,%r10
   0x7fe8fa12651b:  callq  *%r10

which is a difference of one cmp/branch-not-taken. This will
be lost in the noise of having to exit generated code and
look up the next TB anyway.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 1491844419-12485-9-git-send-email-peter.maydell@linaro.org
2017-04-20 17:39:17 +01:00
Peter Maydell
064c379c99 arm: Track M profile handler mode state in TB flags
For M profile exception-return handling we'd like to generate different
code for some instructions depending on whether we are in Handler
mode or Thread mode. This isn't the same as "are we privileged
or user", so we need an extra bit in the TB flags to distinguish.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 1491844419-12485-8-git-send-email-peter.maydell@linaro.org
2017-04-20 17:39:17 +01:00