We have for some time had code within the tcg backends to
handle large positive offsets from env. This move makes
sure that need not happen. Indeed, we are able to assert
at build time that simple offsets suffice for all hosts.
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Move all softmmu tlb data into this structure. Arrange the
members so that we are able to place mask+table together and
at a smaller absolute offset from ENV.
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This instruction raises #GP, aka SIGSEGV, if the effective address
is not aligned to 16-bytes.
We have assertions in tcg-op-gvec.c that the offset from ENV is
aligned, for vector types <= V128. But the offset itself does not
validate that the final pointer is aligned -- one must also remember
to use the QEMU_ALIGNED() attribute on the vector member within ENV.
PowerPC Altivec has vector load/store instructions that silently
discard the low 4 bits of the address, making alignment mistakes
difficult to discover. Aid that by making the most popular host
visibly signal the error.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
The allows immediates to be used for ORR and BIC,
as well as the trivial inversions, ORC and AND.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Use MOVI+ORR or MVNI+BIC in order to build some vector constants,
as opposed to dropping them to the constant pool. This includes
all 16-bit constants and a similar set of 32-bit constants.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
There are several sub-classes of vector immediate, and only MOVI
can use them all. This will enable usage of MVNI and ORRI, which
use progressively fewer sub-classes.
This patch adds no new functionality, merely splits the function
and moves part of the logic into tcg_out_dupi_vec.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
The instruction set has 3 insns that perform the same operation,
only varying in which operand must overlap the destination. We
can represent the operation without overlap and choose based on
the operands seen.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Using umin(a, b) == a as an expansion for TCG_COND_LEU is a
better alternative to (a - INT_MIN) <= (b - INT_MIN).
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
We already had backend support for this feature. Expand the new
cmpsel opcode using vpblendb. The combination allows us to avoid
an extra NOT for some comparison codes.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
If INDEX_op_foo is always expanded by tcg_expand_vec_op, then
there may be no reasonable set of constraints to return from
tcg_target_op_def for that opcode.
Let TCG_TARGET_HAS_foo be specified as -1 in that case. Thus a
boolean test for TCG_TARGET_HAS_foo is true, but we will not
assert within process_op_defs when no constraints are specified.
Compare this with tcg_can_emit_vec_op, which already uses this
tri-state indication.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Perform a per-element conditional move. This combination operation is
easier to implement on some host vector units than plain cmp+bitsel.
Omit the usual gvec interface, as this is intended to be used by
target-specific gvec expansion call-backs.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This operation performs d = (b & a) | (c & ~a), and is present
on a majority of host vector units. Include gvec expanders.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
The paths through tcg_gen_dup_mem_vec and through MO_128 were
missing the check_size_align. The path through MO_128 was also
missing the expand_clr. This last was not visible because the
only user is ARM SVE, which would set oprsz == maxsz, and not
require the clear.
Fix by adding the check_size_align and using do_dup directly
instead of duplicating the check in tcg_gen_gvec_dup_{i32,i64}.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
The VBROADCASTSD instruction only allows %ymm registers as destination.
Rather than forcing VEX.L and writing to the entire 256-bit register,
revert to using MOVDDUP with an %xmm register. This is sufficient for
an avx1 host since we do not support TCG_TYPE_V256 for that case.
Also fix the 32-bit avx2, which should have used VPBROADCASTW.
Fixes: 1e262b49b5
Tested-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reported-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
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>
Allow expansion either via shift by scalar or by replicating
the scalar for shift by vector.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
v3: Use a private structure for do_gvec_shifts.
The gvec expanders perform a modulo on the shift count. If the target
requires alternate behaviour, then it cannot use the generic gvec
expanders anyway, and will have to have its own custom code.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Allow the backend to expand dup from memory directly, instead of
forcing the value into a temp first. This is especially important
if integer/vector register moves do not exist.
Note that officially tcg_out_dupm_vec is allowed to fail.
If it did, we could fix this up relatively easily:
VECE == 32/64:
Load the value into a vector register, then dup.
Both of these must work.
VECE == 8/16:
If the value happens to be at an offset such that an aligned
load would place the desired value in the least significant
end of the register, go ahead and load w/garbage in high bits.
Load the value w/INDEX_op_ld{8,16}_i32.
Attempt a move directly to vector reg, which may fail.
Store the value into the backing store for OTS.
Load the value into the vector reg w/TCG_TYPE_I32, which must work.
Duplicate from the vector reg into itself, which must work.
All of which is well and good, except that all supported
hosts can support dupm for all vece, so all of the failure
paths would be dead code and untestable.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
The LD1R instruction does all the work. Note that the only
useful addressing mode is a base register with no offset.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This case is similar to INDEX_op_mov_* in that we need to do
different things depending on the current location of the source.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
v3: Added some commentary to the tcg_reg_alloc_* functions.
The i386 backend already has these functions, and the aarch64 backend
could easily split out one. Nothing is done with these functions yet,
but this will aid register allocation of INDEX_op_dup_vec in a later patch.
Adjust the aarch64 tcg_out_dupi_vec signature to match the new interface.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
PowerPC Altivec does not support direct moves between vector registers
and general registers. So when tcg_out_mov fails, we can use the
backing memory for the temporary to perform the move.
Acked-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This patch merely changes the interface, aborting on all failures,
of which there are currently none.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
We have a function that takes an additional condition parameter
over the standard backend interface. It already takes care of
eliding no-op moves.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
The only fixed_reg is cpu_env, and it should not be modified
during any TB. Therefore code that tries to special-case moves
into a fixed_reg is dead. Remove it.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Replace the single opcode in .opc with a null-terminated
array in .opt_opc. We still require that all opcodes be
used with the same .vece.
Validate the contents of this list with CONFIG_DEBUG_TCG.
All tcg_gen_*_vec functions will check any list active
during .fniv expansion. Swap the active list in and out
as we expand other opcodes, or take control away from the
front-end function.
Convert all existing vector aware front ends.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
PowerPC Altivec does not support add and subtract of 64-bit elements.
Prepare for that configuration by not assuming the operation is
universally supported.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Use tcg_can_emit_vec_op instead of just TCG_TARGET_HAS_neg_vec,
so that we check the type and vece for the actual operation.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Let's add tcg_gen_gvec_3i(), similar to tcg_gen_gvec_2i(), however
without introducing "gen_helper_gvec_3i *fnoi", as it isn't needed
for now.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190416185301.25344-2-david@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This will not necessarily restrict the size of the TB, since for v7
the majority of constant pool usage is for calls from the out-of-line
ldst code, which is already at the end of the TB. But this does
allow us to save one insn per reference on the off-chance.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
There is no point in coding for a 2GB offset when the max TB size
is already limited to 64k. If we further restrict to 32k then we
can eliminate the extra ADDIS instruction.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
If the TB generates too much code, such that backend relocations
overflow, try again with a smaller TB. In support of this, move
relocation processing from a random place within tcg_out_op, in
the handling of branch opcodes, to a new function at the end of
tcg_gen_code.
This is not a complete solution, as there are additional relocs
generated for out-of-line ldst handling and constant pools.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
If a TB generates too much code, try again with fewer insns.
Fixes: https://bugs.launchpad.net/bugs/1824853
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
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>
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>
dump_exec_info() takes an fprintf()-like callback and a FILE * to pass
to it.
Its only caller hmp_info_jit() passes monitor_fprintf() and the
current monitor cast to FILE *. monitor_fprintf() casts it right
back, and is otherwise identical to monitor_printf(). The
type-punning is ugly.
Drop the callback, and call qemu_printf() instead.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20190417191805.28198-5-armbru@redhat.com>
dump_opcount_info() takes an fprintf()-like callback and a FILE * to
pass to it.
Its only caller hmp_info_opcount() passes monitor_fprintf() and the
current monitor cast to FILE *. monitor_fprintf() casts it right
back, and is otherwise identical to monitor_printf(). The
type-punning is ugly.
Drop the callback, and call qemu_printf() instead.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20190417191805.28198-4-armbru@redhat.com>
The last update to this file was 9 years ago. In the meantime,
4 of the 6 ideas have actually been completed. The lat two do
not actually make sense anymore.
Suggested-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Due to a cut/paste error in the original implementation, the unsigned
vector saturating arithmetic was erroneously being calculated as signed
vector saturating arithmetic.
Fixes: 8ffafbcec2 ("tcg/i386: Implement vector saturating arithmetic")
Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Message-Id: <20190207224258.426-1-mark.cave-ayland@ilande.co.uk>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Currently, a jump to a label that is not defined anywhere will
be emitted not be relocated. This results in a jump to a random
jump target. With tcg debugging, print a diagnostic to the -d op
file and abort.
This could help debug or detect errors like
c2d9644e6d ("target/arm: Fix crash on conditional instruction in an IT block")
Reported-by: Roman Kapl <code@rkapl.cz>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
It's either "GNU *Library* General Public version 2" or "GNU Lesser
General Public version *2.1*", but there was no "version 2.0" of the
"Lesser" library. So assume that version 2.1 is meant here.
Cc: Richard Henderson <rth@twiddle.net>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <1548252536-6242-5-git-send-email-thuth@redhat.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Now that all tcg backends support TCG_TARGET_IMPLEMENTS_DYN_TLB,
remove the define and the old code.
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Tested-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Disabled in all TCG backends for now.
Tested-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Message-Id: <20190116170114.26802-3-cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
The avx instruction set does not directly provide MO_64.
We can still implement 64-bit with comparison and vpblendvb.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
We handle many of these during integer expansion, and the
rest of them during integer optimization.
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Most files that have TABs only contain a handful of them. Change
them to spaces so that we don't confuse people.
disas, standard-headers, linux-headers and libdecnumber are imported
from other projects and probably should be exempted from the check.
Outside those, after this patch the following files still contain both
8-space and TAB sequences at the beginning of the line. Many of them
have a majority of TABs, or were initially committed with all tabs.
bsd-user/i386/target_syscall.h
bsd-user/x86_64/target_syscall.h
crypto/aes.c
hw/audio/fmopl.c
hw/audio/fmopl.h
hw/block/tc58128.c
hw/display/cirrus_vga.c
hw/display/xenfb.c
hw/dma/etraxfs_dma.c
hw/intc/sh_intc.c
hw/misc/mst_fpga.c
hw/net/pcnet.c
hw/sh4/sh7750.c
hw/timer/m48t59.c
hw/timer/sh_timer.c
include/crypto/aes.h
include/disas/bfd.h
include/hw/sh4/sh.h
libdecnumber/decNumber.c
linux-headers/asm-generic/unistd.h
linux-headers/linux/kvm.h
linux-user/alpha/target_syscall.h
linux-user/arm/nwfpe/double_cpdo.c
linux-user/arm/nwfpe/fpa11_cpdt.c
linux-user/arm/nwfpe/fpa11_cprt.c
linux-user/arm/nwfpe/fpa11.h
linux-user/flat.h
linux-user/flatload.c
linux-user/i386/target_syscall.h
linux-user/ppc/target_syscall.h
linux-user/sparc/target_syscall.h
linux-user/syscall.c
linux-user/syscall_defs.h
linux-user/x86_64/target_syscall.h
slirp/cksum.c
slirp/if.c
slirp/ip.h
slirp/ip_icmp.c
slirp/ip_icmp.h
slirp/ip_input.c
slirp/ip_output.c
slirp/mbuf.c
slirp/misc.c
slirp/sbuf.c
slirp/socket.c
slirp/socket.h
slirp/tcp_input.c
slirp/tcpip.h
slirp/tcp_output.c
slirp/tcp_subr.c
slirp/tcp_timer.c
slirp/tftp.c
slirp/udp.c
slirp/udp.h
target/cris/cpu.h
target/cris/mmu.c
target/cris/op_helper.c
target/sh4/helper.c
target/sh4/op_helper.c
target/sh4/translate.c
tcg/sparc/tcg-target.inc.c
tests/tcg/cris/check_addo.c
tests/tcg/cris/check_moveq.c
tests/tcg/cris/check_swap.c
tests/tcg/multiarch/test-mmap.c
ui/vnc-enc-hextile-template.h
ui/vnc-enc-zywrle.h
util/envlist.c
util/readline.c
The following have only TABs:
bsd-user/i386/target_signal.h
bsd-user/sparc64/target_signal.h
bsd-user/sparc64/target_syscall.h
bsd-user/sparc/target_signal.h
bsd-user/sparc/target_syscall.h
bsd-user/x86_64/target_signal.h
crypto/desrfb.c
hw/audio/intel-hda-defs.h
hw/core/uboot_image.h
hw/sh4/sh7750_regnames.c
hw/sh4/sh7750_regs.h
include/hw/cris/etraxfs_dma.h
linux-user/alpha/termbits.h
linux-user/arm/nwfpe/fpopcode.h
linux-user/arm/nwfpe/fpsr.h
linux-user/arm/syscall_nr.h
linux-user/arm/target_signal.h
linux-user/cris/target_signal.h
linux-user/i386/target_signal.h
linux-user/linux_loop.h
linux-user/m68k/target_signal.h
linux-user/microblaze/target_signal.h
linux-user/mips64/target_signal.h
linux-user/mips/target_signal.h
linux-user/mips/target_syscall.h
linux-user/mips/termbits.h
linux-user/ppc/target_signal.h
linux-user/sh4/target_signal.h
linux-user/sh4/termbits.h
linux-user/sparc64/target_syscall.h
linux-user/sparc/target_signal.h
linux-user/x86_64/target_signal.h
linux-user/x86_64/termbits.h
pc-bios/optionrom/optionrom.h
slirp/mbuf.h
slirp/misc.h
slirp/sbuf.h
slirp/tcp.h
slirp/tcp_timer.h
slirp/tcp_var.h
target/i386/svm.h
target/sparc/asi.h
target/xtensa/core-dc232b/xtensa-modules.inc.c
target/xtensa/core-dc233c/xtensa-modules.inc.c
target/xtensa/core-de212/core-isa.h
target/xtensa/core-de212/xtensa-modules.inc.c
target/xtensa/core-fsf/xtensa-modules.inc.c
target/xtensa/core-sample_controller/core-isa.h
target/xtensa/core-sample_controller/xtensa-modules.inc.c
target/xtensa/core-test_kc705_be/core-isa.h
target/xtensa/core-test_kc705_be/xtensa-modules.inc.c
tests/tcg/cris/check_abs.c
tests/tcg/cris/check_addc.c
tests/tcg/cris/check_addcm.c
tests/tcg/cris/check_addoq.c
tests/tcg/cris/check_bound.c
tests/tcg/cris/check_ftag.c
tests/tcg/cris/check_int64.c
tests/tcg/cris/check_lz.c
tests/tcg/cris/check_openpf5.c
tests/tcg/cris/check_sigalrm.c
tests/tcg/cris/crisutils.h
tests/tcg/cris/sys.c
tests/tcg/i386/test-i386-ssse3.c
ui/vgafont.h
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20181213223737.11793-3-pbonzini@redhat.com>
Reviewed-by: Aleksandar Markovic <amarkovic@wavecomp.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Wainer dos Santos Moschetta <wainersm@redhat.com>
Acked-by: Richard Henderson <richard.henderson@linaro.org>
Acked-by: Eric Blake <eblake@redhat.com>
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Stefan Markovic <smarkovic@wavecomp.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Most list head structs need not be given a name. In most cases the
name is given just in case one is going to use QTAILQ_LAST, QTAILQ_PREV
or reverse iteration, but this does not apply to lists of other kinds,
and even for QTAILQ in practice this is only rarely needed. In addition,
we will soon reimplement those macros completely so that they do not
need a name for the head struct. So clean up everything, not giving a
name except in the rare case where it is necessary.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Free the argument register only after we have verified that the
temporary is not already in that register. This case is likely
now that we are back propagating the preferred register.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
With these preferences, we can arrange for function call arguments to
be computed into the proper registers instead of requiring extra moves.
Reviewed-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Use this to notice the opcodes that exit the TB, which implies
that local temps are really dead and need not be synced.
Previously we so marked the true end of the TB, but that was
immediately overwritten by the la_bb_end invoked by any
TCG_OPF_BB_END opcode, like exit_tb.
Reviewed-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
No need for a "tcg_" prefix for a static function; we already
have another "la_" prefix for indicating liveness analysis.
Pass in nb_globals and nb_temps, as we will already have them
in registers for other loops within the parent function.
Reviewed-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
There are two blocks of the form
if (foo) {
stuff1;
goto bar;
} else {
baz:
stuff2;
}
which have unnecessary and confusing indentation.
Remove the else and unindent stuff2.
Reviewed-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Try harder to honor the output_pref. When we're forced to allocate
a second register for the input, it does not need to use the input
constraint; that will be honored by the register we allocate for the
output and a move is already required.
Reviewed-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Allocate storage for, but do not yet fill in, per-opcode
preferences for the output operands. Pass it in to the
register allocation routines for output operands.
Reviewed-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This new argument will aid register allocation by indicating how
the temporary will be used in future. If the preference cannot
be satisfied, fall back to the constraints of the current insn.
Short circuit the preference when it cannot be satisfied or if
it does not further constrain the operation.
With an eye toward optimizing function call sequences, optimize
for the preferred_reg set containing a single register.
For the moment, all users pass 0 for preference.
Reviewed-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Delete trivially dead code that follows unconditional branches and
noreturn helpers. These can occur either via optimization or via
the structure of a target's translator following an exception.
Reviewed-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
