Commit Graph

75 Commits

Author SHA1 Message Date
Richard Henderson
b53357acb4 tcg: Make use of bswap flags in tcg_gen_qemu_st_*
By removing TCG_BSWAP_IZ we indicate that the input is
not zero-extended, and thus can remove an explicit extend.
By removing TCG_BSWAP_OZ, we allow the implementation to
leave high bits set, which will be ignored by the store.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-06-29 10:04:57 -07:00
Richard Henderson
359feba534 tcg: Make use of bswap flags in tcg_gen_qemu_ld_*
We can perform any required sign-extension via TCG_BSWAP_OS.

Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-06-29 10:04:57 -07:00
Richard Henderson
2b836c2ac1 tcg: Add flags argument to tcg_gen_bswap16_*, tcg_gen_bswap32_i64
Implement the new semantics in the fallback expansion.
Change all callers to supply the flags that keep the
semantics unchanged locally.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-06-29 10:04:57 -07:00
Richard Henderson
587195bd59 tcg: Add flags argument to bswap opcodes
This will eventually simplify front-end usage, and will allow
backends to unset TCG_TARGET_HAS_MEMORY_BSWAP without loss of
optimization.

The argument is added during expansion, not currently exposed to the
front end translators.  The backends currently only support a flags
value of either TCG_BSWAP_IZ, or (TCG_BSWAP_IZ | TCG_BSWAP_OZ),
since they all require zero top bytes and leave them that way.
At the existing call sites we pass in (TCG_BSWAP_IZ | TCG_BSWAP_OZ),
except for the flags-ignored cases of a 32-bit swap of a 32-bit
value and or a 64-bit swap of a 64-bit value, where we pass 0.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-06-29 10:04:57 -07:00
Thomas Huth
2068cabd3f Do not include cpu.h if it's not really necessary
Stop including cpu.h in files that don't need it.

Signed-off-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20210416171314.2074665-4-thuth@redhat.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
2021-05-02 17:24:51 +02:00
Richard Henderson
11d11d61bd tcg: Use tcg_constant_{i32,i64} with tcg int expanders
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-01-13 08:39:08 -10:00
Richard Henderson
eba40358b4 tcg: Return the TB pointer from the rx region from exit_tb
This produces a small pc-relative displacement within the
generated code to the TB structure that preceeds it.

Reviewed-by: Joelle van Dyne <j@getutm.app>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-01-07 05:09:42 -10:00
Richard Henderson
d997143533 tcg: Make DisasContextBase.tb const
There is nothing within the translators that ought to be
changing the TranslationBlock data, so make it const.

This does not actually use the read-only copy of the
data structure that exists within the rx region.

Reviewed-by: Joelle van Dyne <j@getutm.app>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-01-07 05:09:41 -10:00
Richard Henderson
07ce0b0530 tcg: Introduce INDEX_op_qemu_st8_i32
Enable this on i386 to restrict the set of input registers
for an 8-bit store, as required by the architecture.  This
removes the last use of scratch registers for user-only mode.

Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-01-07 05:09:06 -10:00
Richard Henderson
852f933e48 tcg: Fix do_nonatomic_op_* vs signed operations
The smin/smax/umin/umax operations require the operands to be
properly sign extended.  Do not drop the MO_SIGN bit from the
load, and additionally extend the val input.

Reviewed-by: LIU Zhiwei <zhiwei_liu@c-sky.com>
Reported-by: LIU Zhiwei <zhiwei_liu@c-sky.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20200701165646.1901320-1-richard.henderson@linaro.org>
2020-07-06 10:58:19 -07:00
Richard Henderson
07dada0336 tcg: Fix integral argument type to tcg_gen_rot[rl]i_i{32,64}
For the benefit of compatibility of function pointer types,
we have standardized on int32_t and int64_t as the integral
argument to tcg expanders.

We converted most of them in 474b2e8f0f, but missed the rotates.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2020-05-06 09:25:10 -07:00
Alex Bennée
fcc54ab5c7 tcg: save vaddr temp for plugin usage
While do_gen_mem_cb does copy (via extu_tl_i64) vaddr into a new temp
this won't help if the vaddr temp gets clobbered by the actual
load/store op. To avoid this clobbering we explicitly copy vaddr
before the op to ensure it is live my the time we do the
instrumentation.

Suggested-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Emilio G. Cota <cota@braap.org>
Cc: qemu-stable@nongnu.org
Message-Id: <20200225124710.14152-18-alex.bennee@linaro.org>
2020-02-25 20:20:23 +00:00
Philippe Mathieu-Daudé
dcb32f1d8f tcg: Search includes from the project root source directory
We currently search both the root and the tcg/ directories for tcg
files:

  $ git grep '#include "tcg/' | wc -l
  28

  $ git grep '#include "tcg[^/]' | wc -l
  94

To simplify the preprocessor search path, unify by expliciting the
tcg/ directory.

Patch created mechanically by running:

  $ for x in \
      tcg.h tcg-mo.h tcg-op.h tcg-opc.h \
      tcg-op-gvec.h tcg-gvec-desc.h; do \
    sed -i "s,#include \"$x\",#include \"tcg/$x\"," \
      $(git grep -l "#include \"$x\""); \
    done

Acked-by: David Gibson <david@gibson.dropbear.id.au> (ppc parts)
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Stefan Weil <sw@weilnetz.de>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20200101112303.20724-2-philmd@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2020-01-15 15:13:10 -10:00
Emilio G. Cota
e6d86bed50 tcg: let plugins instrument virtual memory accesses
To capture all memory accesses we need hook into all the various
helper functions that are involved in memory operations as well as the
injected inline helper calls. A later commit will allow us to resolve
the actual guest HW addresses by replaying the lookup.

Signed-off-by: Emilio G. Cota <cota@braap.org>
[AJB: drop haddr handling, just deal in vaddr]
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2019-10-28 15:12:38 +00:00
Alex Bennée
504f73f7b3 trace: add mmu_index to mem_info
We are going to re-use mem_info later for plugins and will need to
track the mmu_idx for softmmu code.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
2019-10-28 15:12:38 +00:00
Tony Nguyen
14776ab5a1 tcg: TCGMemOp is now accelerator independent MemOp
Preparation for collapsing the two byte swaps, adjust_endianness and
handle_bswap, along the I/O path.

Target dependant attributes are conditionalized upon NEED_CPU_H.

Signed-off-by: Tony Nguyen <tony.nguyen@bt.com>
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <81d9cd7d7f5aaadfa772d6c48ecee834e9cf7882.1566466906.git.tony.nguyen@bt.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2019-09-03 08:30:38 -07:00
Markus Armbruster
a8d2532645 Include qemu-common.h exactly where needed
No header includes qemu-common.h after this commit, as prescribed by
qemu-common.h's file comment.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20190523143508.25387-5-armbru@redhat.com>
[Rebased with conflicts resolved automatically, except for
include/hw/arm/xlnx-zynqmp.h hw/arm/nrf51_soc.c hw/arm/msf2-soc.c
block/qcow2-refcount.c block/qcow2-cluster.c block/qcow2-cache.c
target/arm/cpu.h target/lm32/cpu.h target/m68k/cpu.h target/mips/cpu.h
target/moxie/cpu.h target/nios2/cpu.h target/openrisc/cpu.h
target/riscv/cpu.h target/tilegx/cpu.h target/tricore/cpu.h
target/unicore32/cpu.h target/xtensa/cpu.h; bsd-user/main.c and
net/tap-bsd.c fixed up]
2019-06-12 13:20:20 +02:00
Richard Henderson
ff1f11f7f8 tcg: Add support for integer absolute value
Remove a function of the same name from target/arm/.
Use a branchless implementation of abs gleaned from gcc.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2019-05-13 22:52:08 +00:00
Richard Henderson
b0a6056719 tcg: Use extract2 in tcg_gen_deposit_{i32,i64}
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2019-04-24 13:04:33 -07:00
Richard Henderson
02616bad6f tcg: Use deposit and extract2 in tcg_gen_shifti_i64
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2019-04-24 13:04:33 -07:00
Richard Henderson
fce1296f13 tcg: Add INDEX_op_extract2_{i32,i64}
This will let backends implement the double-word shift operation.

Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2019-04-24 13:04:33 -07:00
David Hildenbrand
2089fcc9e7 tcg: Implement tcg_gen_extract2_{i32,i64}
Will be helpful for s390x. Input 128 bit and output 64 bit only,
which is sufficient for now.

Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190225154204.26751-1-david@redhat.com>
[rth: Add matching tcg_gen_extract2_i32.]
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2019-04-24 13:04:33 -07:00
Richard Henderson
d88a117eaa tcg: Reference count labels
Increment when adding branches, and decrement when removing them.

Reviewed-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2018-12-26 06:40:27 +11:00
Richard Henderson
e1dcf3529d tcg: Add TCG_TARGET_HAS_MEMORY_BSWAP
For now, defined universally as true, since we previously required
backends to implement swapped memory operations.  Future patches
may now remove that support where it is onerous.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2018-12-17 06:04:44 +03:00
Richard Henderson
9e821eab0a tcg: Clean up generic bswap64
Based on the only current user, Sparc:

New code uses 2 constants that take 2 insns to load from constant pool,
plus 13.  Old code used 6 constants that took 1 or 2 insns to create,
plus 21.  The result is a new total of 17 vs an old total of 29.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2018-12-17 06:04:44 +03:00
Richard Henderson
a686dc71d8 tcg: Clean up generic bswap32
Based on the only current user, Sparc:

New code uses 1 constant that takes 2 insns to create, plus 8.
Old code used 2 constants that took 2 insns to create, plus 9.
The result is a new total of 10 vs an old total of 13.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2018-12-17 06:04:44 +03:00
Richard Henderson
d7f425fdea tcg: Implement CPU_LOG_TB_NOCHAIN during expansion
Rather than test NOCHAIN before linking, do not emit the
goto_tb opcode at all.  We already do this for goto_ptr.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2018-10-18 18:58:10 -07:00
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
Richard Henderson
5507c2bf35 tcg: Introduce atomic helpers for integer min/max
Given that this atomic operation will be used by both risc-v
and aarch64, let's not duplicate code across the two targets.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20180508151437.4232-5-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-05-10 18:10:57 +01:00
Richard Henderson
b87fb8cd9f tcg: Introduce helpers for integer min/max
These operations are re-invented by several targets so far.
Several supported hosts have insns for these, so place the
expanders out-of-line for a future introduction of tcg opcodes.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20180508151437.4232-2-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-05-10 18:10:57 +01:00
Richard Henderson
b2e3ae9452 tcg: Improve tcg_gen_muli_i32/i64
Convert multiplication by power of two to left shift.

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>
2018-03-16 00:55:04 +08:00
Richard Henderson
474b2e8f0f tcg: Standardize integral arguments to expanders
Some functions use intN_t arguments, some use uintN_t, some just
used "unsigned".  To aid putting function pointers in tables, we
need consistency.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2018-02-08 15:54:05 +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
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
e82d5a2460 tcg: check CF_PARALLEL instead of parallel_cpus
Thereby decoupling the resulting translated code from the current state
of the system.

The tb->cflags field is not passed to tcg generation functions. So
we add a field to TCGContext, storing there a copy of tb->cflags.

Most architectures have <= 32 registers, which results in a 4-byte hole
in TCGContext. Use this hole for the new field.

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
Richard Henderson
dc41aa7d34 tcg: Remove GET_TCGV_* and MAKE_TCGV_*
The GET and MAKE functions weren't really specific enough.
We now have a full complement of functions that convert exactly
between temporaries, arguments, tcgv pointers, and indices.

The target/sparc change is also a bug fix, which would have affected
a host that defines TCG_TARGET_HAS_extr[lh]_i64_i32, i.e. MIPS64.

Reviewed-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2017-10-24 21:49:30 +02:00
Richard Henderson
ae8b75dc6e tcg: Introduce tcgv_{i32,i64,ptr}_{arg,temp}
Transform TCGv_* to an "argument" or a temporary.
For now, an argument is simply the temporary index.

Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2017-10-24 21:47:46 +02:00
Richard Henderson
b7e8b17a77 tcg: Push tcg_ctx into generator functions
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2017-10-24 21:45:07 +02:00
Richard Henderson
75e8b9b7aa tcg: Merge opcode arguments into TCGOp
Rather than have a separate buffer of 10*max_ops entries,
give each opcode 10 entries.  The result is actually a bit
smaller and should have slightly more cache locality.

Reviewed-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-10-24 21:34:47 +02:00
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
Pranith Kumar
b32dc3370a tcg: Implement implicit ordering semantics
Currently, we cannot use mttcg for running strong memory model guests
on weak memory model hosts due to missing ordering semantics.

We implicitly generate fence instructions for stronger guests if an
ordering mismatch is detected. We generate fences only for the orders
for which fence instructions are necessary, for example a fence is not
necessary between a store and a subsequent load on x86 since its
absence in the guest binary tells that ordering need not be
ensured. Also note that if we find multiple subsequent fence
instructions in the generated IR, we combine them in the TCG
optimization pass.

This patch allows us to boot an x86 guest on ARM64 hosts using mttcg.

Signed-off-by: Pranith Kumar <bobby.prani@gmail.com>
Message-Id: <20170829063313.10237-4-bobby.prani@gmail.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2017-09-05 13:41:46 -07:00
Emilio G. Cota
cedbcb0152 tcg: Introduce goto_ptr opcode and tcg_gen_lookup_and_goto_ptr
Instead of exporting goto_ptr directly to TCG frontends, export
tcg_gen_lookup_and_goto_ptr(), which calls goto_ptr with the pointer
returned by the lookup_tb_ptr() helper. This is the only use case
we have for goto_ptr and lookup_tb_ptr, so having this function is
very convenient. Furthermore, it trivially allows us to avoid calling
the lookup helper if goto_ptr is not implemented by the backend.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Message-Id: <1493263764-18657-2-git-send-email-cota@braap.org>
Message-Id: <1493263764-18657-3-git-send-email-cota@braap.org>
Message-Id: <1493263764-18657-4-git-send-email-cota@braap.org>
Message-Id: <1493263764-18657-5-git-send-email-cota@braap.org>
[rth: Squashed 4 related commits.]
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-06-05 09:25:42 -07:00
Richard Henderson
79b1af9062 tcg: Initialize return value after exit_atomic
Users of tcg_gen_atomic_cmpxchg and do_atomic_op rightfully utilize
the output.  Even though this code is dead, it gets translated, and
without the initialization we encounter a tcg_error.

Reported-by: Nikunj A Dadhania <nikunj@linux.vnet.ibm.com>
Tested-by: Nikunj A Dadhania <nikunj@linux.vnet.ibm.com>
Tested-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-04-26 19:26:11 +02:00
Richard Henderson
14e99210f6 tcg: Use ctpop to generate ctz if needed
Particularly when andc is also available, this is two insns
shorter than using clz to compute ctz.

Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-01-10 08:49:59 -08:00
Richard Henderson
a768e4e992 tcg: Add opcode for ctpop
The number of actual invocations of ctpop itself does not warrent
an opcode, but it is very helpful for POWER7 to use in generating
an expansion for ctz.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-01-10 08:48:56 -08:00
Richard Henderson
086920c2c8 tcg: Add helpers for clrsb
The number of actual invocations does not warrent an opcode,
and the backends generating it.  But at least we can eliminate
redundant helpers.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-01-10 08:47:48 -08:00
Richard Henderson
0e28d0063b tcg: Add clz and ctz opcodes
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-01-10 08:06:11 -08:00
Richard Henderson
07cc68d528 tcg: Add deposit_z expander
While we don't require a new opcode, it is handy to have an expander
that knows the first source is zero.

Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-01-10 07:59:11 -08:00
Richard Henderson
0d0d309df0 tcg: Minor adjustments to deposit expanders
Assert that len is not 0.

Since we have asserted that ofs + len <= N, a later
check for len == N implies that ofs == 0.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-01-10 07:59:11 -08:00