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2016-01-29tcg: Clean up includesPeter Maydell
Clean up includes so that osdep.h is included first and headers which it implies are not included manually. This commit was created with scripts/clean-includes. Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Message-id: 1453832250-766-16-git-send-email-peter.maydell@linaro.org
2015-08-24tcg: Split trunc_shr_i32 opcode into extr[lh]_i64_i32Richard Henderson
Rather than allow arbitrary shift+trunc, only concern ourselves with low and high parts. This is all that was being used anyway. Signed-off-by: Richard Henderson <rth@twiddle.net>
2015-08-24tcg/optimize: add optimizations for ext_i32_i64 and extu_i32_i64 opsAurelien Jarno
They behave the same as ext32s_i64 and ext32u_i64 from the constant folding and zero propagation point of view, except that they can't be replaced by a mov, so we don't compute the affected value. Signed-off-by: Aurelien Jarno <aurelien@aurel32.net> Signed-off-by: Richard Henderson <rth@twiddle.net>
2015-08-24tcg: rename trunc_shr_i32 into trunc_shr_i64_i32Aurelien Jarno
The op is sometimes named trunc_shr_i32 and sometimes trunc_shr_i64_i32, and the name in the README doesn't match the name offered to the frontends. Always use the long name to make it clear it is a size changing op. Signed-off-by: Aurelien Jarno <aurelien@aurel32.net> Signed-off-by: Richard Henderson <rth@twiddle.net>
2015-08-24tcg/optimize: allow constant to have copiesAurelien Jarno
Now that copies and constants are tracked separately, we can allow constant to have copies, deferring the choice to use a register or a constant to the register allocation pass. This prevent this kind of regular constant reloading: -OUT: [size=338] +OUT: [size=298] mov -0x4(%r14),%ebp test %ebp,%ebp jne 0x7ffbe9cb0ed6 mov $0x40002219f8,%rbp mov %rbp,(%r14) - mov $0x40002219f8,%rbp mov $0x4000221a20,%rbx mov %rbp,(%rbx) mov $0x4000000000,%rbp mov %rbp,(%r14) - mov $0x4000000000,%rbp mov $0x4000221d38,%rbx mov %rbp,(%rbx) mov $0x40002221a8,%rbp mov %rbp,(%r14) - mov $0x40002221a8,%rbp mov $0x4000221d40,%rbx mov %rbp,(%rbx) mov $0x4000019170,%rbp mov %rbp,(%r14) - mov $0x4000019170,%rbp mov $0x4000221d48,%rbx mov %rbp,(%rbx) mov $0x40000049ee,%rbp mov %rbp,0x80(%r14) mov %r14,%rdi callq 0x7ffbe99924d0 mov $0x4000001680,%rbp mov %rbp,0x30(%r14) mov 0x10(%r14),%rbp mov $0x4000001680,%rbp mov %rbp,0x30(%r14) mov 0x10(%r14),%rbp shl $0x20,%rbp mov (%r14),%rbx mov %ebx,%ebx mov %rbx,(%r14) or %rbx,%rbp mov %rbp,0x10(%r14) mov %rbp,0x90(%r14) mov 0x60(%r14),%rbx mov %rbx,0x38(%r14) mov 0x28(%r14),%rbx mov $0x4000220e60,%r12 mov %rbx,(%r12) mov $0x40002219c8,%rbx mov %rbp,(%rbx) mov 0x20(%r14),%rbp sub $0x8,%rbp mov $0x4000004a16,%rbx mov %rbx,0x0(%rbp) mov %rbp,0x20(%r14) mov $0x19,%ebp mov %ebp,0xa8(%r14) mov $0x4000015110,%rbp mov %rbp,0x80(%r14) xor %eax,%eax jmpq 0x7ffbebcae426 lea -0x5f6d72a(%rip),%rax # 0x7ffbe3d437b3 jmpq 0x7ffbebcae426 Signed-off-by: Aurelien Jarno <aurelien@aurel32.net> Signed-off-by: Richard Henderson <rth@twiddle.net>
2015-08-24tcg/optimize: track const/copy status separatelyAurelien Jarno
Instead of using an enum which could be either a copy or a const, track them separately. This will be used in the next patch. Constants are tracked through a bool. Copies are tracked by initializing temp's next_copy and prev_copy to itself, allowing to simplify the code a bit. Signed-off-by: Aurelien Jarno <aurelien@aurel32.net> Signed-off-by: Richard Henderson <rth@twiddle.net>
2015-08-24tcg/optimize: add temp_is_const and temp_is_copy functionsAurelien Jarno
Add two accessor functions temp_is_const and temp_is_copy, to make the code more readable and make code change easier. Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Aurelien Jarno <aurelien@aurel32.net> Signed-off-by: Richard Henderson <rth@twiddle.net>
2015-08-24tcg/optimize: optimize temps trackingAurelien Jarno
The tcg_temp_info structure uses 24 bytes per temp. Now that we emulate vector registers on most guests, it's not uncommon to have more than 100 used temps. This means we have initialize more than 2kB at least twice per TB, often more when there is a few goto_tb. Instead used a TCGTempSet bit array to track which temps are in used in the current basic block. This means there are only around 16 bytes to initialize. This improves the boot time of a MIPS guest on an x86-64 host by around 7% and moves out tcg_optimize from the the top of the profiler list. [rth: Handle TCG_CALL_DUMMY_ARG] Signed-off-by: Aurelien Jarno <aurelien@aurel32.net> Signed-off-by: Richard Henderson <rth@twiddle.net>
2015-08-24tcg/optimize: fix constant signednessAurelien Jarno
By convention, on a 64-bit host TCG internally stores 32-bit constants as sign-extended. This is not the case in the optimizer when a 32-bit constant is folded. This doesn't seem to have more consequences than suboptimal code generation. For instance the x86 backend assumes sign-extended constants, and in some rare cases uses a 32-bit unsigned immediate 0xffffffff instead of a 8-bit signed immediate 0xff for the constant -1. This is with a ppc guest: before ------ ---- 0x9f29cc movi_i32 tmp1,$0xffffffff movi_i32 tmp2,$0x0 add2_i32 tmp0,CA,CA,tmp2,r6,tmp2 add2_i32 tmp0,CA,tmp0,CA,tmp1,tmp2 mov_i32 r10,tmp0 0x7fd8c7dfe90c: xor %ebp,%ebp 0x7fd8c7dfe90e: mov %ebp,%r11d 0x7fd8c7dfe911: mov 0x18(%r14),%r9d 0x7fd8c7dfe915: add %r9d,%r10d 0x7fd8c7dfe918: adc %ebp,%r11d 0x7fd8c7dfe91b: add $0xffffffff,%r10d 0x7fd8c7dfe922: adc %ebp,%r11d 0x7fd8c7dfe925: mov %r11d,0x134(%r14) 0x7fd8c7dfe92c: mov %r10d,0x28(%r14) after ----- ---- 0x9f29cc movi_i32 tmp1,$0xffffffffffffffff movi_i32 tmp2,$0x0 add2_i32 tmp0,CA,CA,tmp2,r6,tmp2 add2_i32 tmp0,CA,tmp0,CA,tmp1,tmp2 mov_i32 r10,tmp0 0x7f37010d490c: xor %ebp,%ebp 0x7f37010d490e: mov %ebp,%r11d 0x7f37010d4911: mov 0x18(%r14),%r9d 0x7f37010d4915: add %r9d,%r10d 0x7f37010d4918: adc %ebp,%r11d 0x7f37010d491b: add $0xffffffffffffffff,%r10d 0x7f37010d491f: adc %ebp,%r11d 0x7f37010d4922: mov %r11d,0x134(%r14) 0x7f37010d4929: mov %r10d,0x28(%r14) Signed-off-by: Aurelien Jarno <aurelien@aurel32.net> Message-Id: <1436544211-2769-2-git-send-email-aurelien@aurel32.net> Signed-off-by: Richard Henderson <rth@twiddle.net>
2015-07-23tcg/optimize: fix tcg_opt_gen_moviAurelien Jarno
Due to a copy&paste, the new op value is tested against mov_i32 instead of movi_i32. The test is therefore always false. Fix that. Signed-off-by: Aurelien Jarno <aurelien@aurel32.net> Message-Id: <1436544211-2769-1-git-send-email-aurelien@aurel32.net> Signed-off-by: Richard Henderson <rth@twiddle.net>
2015-06-09tcg/optimize: rename tcg_constant_foldingAurelien Jarno
The tcg_constant_folding folding ends up doing all the optimizations (which is a good thing to avoid looping on all ops multiple time), so make it clear and just rename it tcg_optimize. Cc: Richard Henderson <rth@twiddle.net> Signed-off-by: Aurelien Jarno <aurelien@aurel32.net> Message-Id: <1433447607-31184-6-git-send-email-aurelien@aurel32.net> Signed-off-by: Richard Henderson <rth@twiddle.net>
2015-06-09tcg/optimize: fold constant test in tcg_opt_gen_movAurelien Jarno
Most of the calls to tcg_opt_gen_mov are preceeded by a test to check if the source temp is a constant. Fold that into the tcg_opt_gen_mov function. Cc: Richard Henderson <rth@twiddle.net> Signed-off-by: Aurelien Jarno <aurelien@aurel32.net> Message-Id: <1433495958-9508-1-git-send-email-aurelien@aurel32.net> Signed-off-by: Richard Henderson <rth@twiddle.net>
2015-06-09tcg/optimize: fold temp copies test in tcg_opt_gen_movAurelien Jarno
Each call to tcg_opt_gen_mov is preceeded by a test to check if the source and destination temps are copies. Fold that into the tcg_opt_gen_mov function. Cc: Richard Henderson <rth@twiddle.net> Signed-off-by: Aurelien Jarno <aurelien@aurel32.net> Message-Id: <1433447607-31184-4-git-send-email-aurelien@aurel32.net> Signed-off-by: Richard Henderson <rth@twiddle.net>
2015-06-09tcg/optimize: remove opc argument from tcg_opt_gen_movAurelien Jarno
We can get the opcode using the TCGOp pointer. It needs to be dereferenced, but it's anyway done a few lines below to write the new value. Cc: Richard Henderson <rth@twiddle.net> Signed-off-by: Aurelien Jarno <aurelien@aurel32.net> Message-Id: <1433447607-31184-3-git-send-email-aurelien@aurel32.net> Signed-off-by: Richard Henderson <rth@twiddle.net>
2015-06-09tcg/optimize: remove opc argument from tcg_opt_gen_moviAurelien Jarno
We can get the opcode using the TCGOp pointer. It needs to be dereferenced, but it's anyway done a few lines below to write the new value. Cc: Richard Henderson <rth@twiddle.net> Signed-off-by: Aurelien Jarno <aurelien@aurel32.net> Message-Id: <1433447607-31184-2-git-send-email-aurelien@aurel32.net> Signed-off-by: Richard Henderson <rth@twiddle.net>
2015-05-14tcg: Merge memop and mmu_idx parameters to qemu_ld/stRichard Henderson
At the tcg opcode level, not at the tcg-op.h generator level. This requires minor changes through all of the tcg backends, but none of the cpu translators. Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Richard Henderson <rth@twiddle.net>
2015-03-16tcg/optimize: Handle or r,a,a with constant aRichard Henderson
As seen with ubuntu-5.10-live-powerpc.iso. Reported-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk> Tested-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk> Reviewed-by: Bastian Koppelmann <kbastian@mail.uni-paderborn.de> Signed-off-by: Richard Henderson <rth@twiddle.net>
2015-02-12tcg: Implement insert_op_beforeRichard Henderson
Rather reserving space in the op stream for optimization, let the optimizer add ops as necessary. Reviewed-by: Bastian Koppelmann <kbastian@mail.uni-paderborn.de> Signed-off-by: Richard Henderson <rth@twiddle.net>
2015-02-12tcg: Remove opcodes instead of noping them outRichard Henderson
With the linked list scheme we need not leave nops in the stream that we need to process later. Reviewed-by: Bastian Koppelmann <kbastian@mail.uni-paderborn.de> Signed-off-by: Richard Henderson <rth@twiddle.net>
2015-02-12tcg: Put opcodes in a linked listRichard Henderson
The previous setup required ops and args to be completely sequential, and was error prone when it came to both iteration and optimization. Reviewed-by: Bastian Koppelmann <kbastian@mail.uni-paderborn.de> Signed-off-by: Richard Henderson <rth@twiddle.net>
2014-06-18tcg/optimize: Don't special case TCG_OPF_CALL_CLOBBERRichard Henderson
With the "old" ldst ops we didn't know the real width of the result of the load, but with the "new" ldst ops we do. Signed-off-by: Richard Henderson <rth@twiddle.net>
2014-06-04tcg: Remove TCG_TARGET_HAS_new_ldstRichard Henderson
Since all backends have been converted, remove the compatibility code. Acked-by: Claudio Fontana <claudio.fontana@huawei.com> Signed-off-by: Richard Henderson <rth@twiddle.net>
2014-05-28tcg/optimize: Remember garbage high bits for 32-bit opsRichard Henderson
For a 64-bit host, the high bits of a register after a 32-bit operation are undefined. Adjust the temps mask for all 32-bit ops to reflect that. Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Richard Henderson <rth@twiddle.net>
2014-05-28tcg/optimize: Move updating of gen_opc_buf into tcg_opt_gen_mov*Richard Henderson
No functional change, just reduce a bit of redundancy. Signed-off-by: Richard Henderson <rth@twiddle.net>
2014-05-28tcg: Optimize brcond2 and setcond2 ne/eqRichard Henderson
If either the high or low pair can be resolved, we can simplify to either a constant or to a 32-bit comparison. Signed-off-by: Richard Henderson <rth@twiddle.net>
2014-05-12tcg: Make call address a constant parameterRichard Henderson
Avoid allocating a tcg temporary to hold the constant address, and instead place it directly into the op_call arguments. At the same time, convert to the newly introduced tcg_out_call backend function, rather than invoking tcg_out_op for the call. Signed-off-by: Richard Henderson <rth@twiddle.net>
2014-04-28tcg: Add INDEX_op_trunc_shr_i32Richard Henderson
Let the backend do something special for truncation. Signed-off-by: Richard Henderson <rth@twiddle.net>
2014-04-18tcg: Fix out of range shift in deposit optimizationsRichard Henderson
By inspection, for a deposit(x, y, 0, 64), we'd have a shift of (1<<64) and everything else falls apart. But we can reuse the existing deposit logic to get this right. Signed-off-by: Richard Henderson <rth@twiddle.net>
2014-04-18tcg: Mask shift quantities while foldingRichard Henderson
The TCG result would be undefined, but we can at least produce one plausible result and avoid triggering the wrath of analysis tools. Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Richard Henderson <rth@twiddle.net>
2014-02-17tcg/optimize: Add more identity simplificationsRichard Henderson
Recognize 0 operand to andc, and -1 operands to and, orc, eqv. Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Aurelien Jarno <aurelien@aurel32.net> Signed-off-by: Richard Henderson <rth@twiddle.net>
2014-02-17tcg/optimize: Optmize ANDC X,Y,Y to MOV X,0Richard Henderson
Like we already do for SUB and XOR. Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Aurelien Jarno <aurelien@aurel32.net> Signed-off-by: Richard Henderson <rth@twiddle.net>
2014-02-17tcg/optimize: Simply some logical ops to NOTRichard Henderson
Given, of course, an appropriate constant. These could be generated from the "canonical" operation for inversion on the guest, or via other optimizations. Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Aurelien Jarno <aurelien@aurel32.net> Signed-off-by: Richard Henderson <rth@twiddle.net>
2014-02-17tcg/optimize: Handle known-zeros masks for ANDCRichard Henderson
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Aurelien Jarno <aurelien@aurel32.net> Signed-off-by: Richard Henderson <rth@twiddle.net>
2014-02-17tcg/optimize: add known-zero bits compute for load opsAurelien Jarno
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Aurelien Jarno <aurelien@aurel32.net> Signed-off-by: Richard Henderson <rth@twiddle.net>
2014-02-17tcg/optimize: improve known-zero bits for 32-bit opsAurelien Jarno
The shl_i32 op might set some bits of the unused 32 high bits of the mask. Fix that by clearing the unused 32 high bits for all 32-bit ops except load/store which operate on tl values. Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Aurelien Jarno <aurelien@aurel32.net> Signed-off-by: Richard Henderson <rth@twiddle.net>
2014-02-17tcg/optimize: fix known-zero bits optimizationAurelien Jarno
Known-zero bits optimization is a great idea that helps to generate more optimized code. However the current implementation only works in very few cases as the computed mask is not saved. Fix this to make it really working. Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Aurelien Jarno <aurelien@aurel32.net> Signed-off-by: Richard Henderson <rth@twiddle.net>
2014-02-17tcg/optimize: fix known-zero bits for right shift opsAurelien Jarno
32-bit versions of sar and shr ops should not propagate known-zero bits from the unused 32 high bits. For sar it could even lead to wrong code being generated. Cc: qemu-stable@nongnu.org Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Aurelien Jarno <aurelien@aurel32.net> Signed-off-by: Richard Henderson <rth@twiddle.net>
2013-09-25misc: Use new rotate functionsStefan Weil
Signed-off-by: Stefan Weil <sw@weilnetz.de>
2013-09-02tcg: Constant fold div, remRichard Henderson
Reviewed-by: Aurelien Jarno <aurelien@aurel32.net> Signed-off-by: Richard Henderson <rth@twiddle.net>
2013-09-02tcg: Add muluh and mulsh opcodesRichard Henderson
Use them in places where mulu2 and muls2 are used. Optimize mulx2 with dead low part to mulxh. Reviewed-by: Aurelien Jarno <aurelien@aurel32.net> Signed-off-by: Richard Henderson <rth@twiddle.net>
2013-05-09tcg/optimize: fix setcond2 optimizationAurelien Jarno
When setcond2 is rewritten into setcond, the state of the destination temp should be reset, so that a copy of the previous value is not used instead of the result. Reported-by: Michael Tokarev <mjt@tls.msk.ru> Reviewed-by: Richard Henderson <rth@twiddle.net> Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2013-03-23tcg-optimize: Fold sub r,0,x to neg r,xRichard Henderson
Cc: Blue Swirl <blauwirbel@gmail.com> Signed-off-by: Richard Henderson <rth@twiddle.net> Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2013-02-23tcg: Add signed multiword multiplication operationsRichard Henderson
Signed-off-by: Richard Henderson <rth@twiddle.net> Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2013-02-23tcg: Add 64-bit multiword arithmetic operationsRichard Henderson
Matching the 32-bit multiword arithmetic that we already have. Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2013-01-19optimize: optimize using nonzero bitsPaolo Bonzini
This adds two optimizations using the non-zero bit mask. In some cases involving shifts or ANDs the value can become zero, and can thus be optimized to a move of zero. Second, useless zero-extension or an AND with constant can be detected that would only zero bits that are already zero. The main advantage of this optimization is that it turns zero-extensions into moves, thus enabling much better copy propagation (around 1% code reduction). Here is for example a "test $0xff0000,%ecx + je" before optimization: mov_i64 tmp0,rcx movi_i64 tmp1,$0xff0000 discard cc_src and_i64 cc_dst,tmp0,tmp1 movi_i32 cc_op,$0x1c ext32u_i64 tmp0,cc_dst movi_i64 tmp12,$0x0 brcond_i64 tmp0,tmp12,eq,$0x0 and after (without patch on the left, with on the right): movi_i64 tmp1,$0xff0000 movi_i64 tmp1,$0xff0000 discard cc_src discard cc_src and_i64 cc_dst,rcx,tmp1 and_i64 cc_dst,rcx,tmp1 movi_i32 cc_op,$0x1c movi_i32 cc_op,$0x1c ext32u_i64 tmp0,cc_dst movi_i64 tmp12,$0x0 movi_i64 tmp12,$0x0 brcond_i64 tmp0,tmp12,eq,$0x0 brcond_i64 cc_dst,tmp12,eq,$0x0 Other similar cases: "test %eax, %eax + jne" where eax is already 32-bit (after optimization, without patch on the left, with on the right): discard cc_src discard cc_src mov_i64 cc_dst,rax mov_i64 cc_dst,rax movi_i32 cc_op,$0x1c movi_i32 cc_op,$0x1c ext32u_i64 tmp0,cc_dst movi_i64 tmp12,$0x0 movi_i64 tmp12,$0x0 brcond_i64 tmp0,tmp12,ne,$0x0 brcond_i64 rax,tmp12,ne,$0x0 "test $0x1, %dl + je": movi_i64 tmp1,$0x1 movi_i64 tmp1,$0x1 discard cc_src discard cc_src and_i64 cc_dst,rdx,tmp1 and_i64 cc_dst,rdx,tmp1 movi_i32 cc_op,$0x1a movi_i32 cc_op,$0x1a ext8u_i64 tmp0,cc_dst movi_i64 tmp12,$0x0 movi_i64 tmp12,$0x0 brcond_i64 tmp0,tmp12,eq,$0x0 brcond_i64 cc_dst,tmp12,eq,$0x0 In some cases TCG even outsmarts GCC. :) Here the input code has "and $0x2,%eax + movslq %eax,%rbx + test %rbx, %rbx" and the optimizer, thanks to copy propagation, does the following: movi_i64 tmp12,$0x2 movi_i64 tmp12,$0x2 and_i64 rax,rax,tmp12 and_i64 rax,rax,tmp12 mov_i64 cc_dst,rax mov_i64 cc_dst,rax ext32s_i64 tmp0,rax -> nop mov_i64 rbx,tmp0 -> mov_i64 rbx,cc_dst and_i64 cc_dst,rbx,rbx -> nop Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Richard Henderson <rth@twiddle.net> Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2013-01-19optimize: track nonzero bits of registersPaolo Bonzini
Add a "mask" field to the tcg_temp_info struct. A bit that is zero in "mask" will always be zero in the corresponding temporary. Zero bits in the mask can be produced from moves of immediates, zero-extensions, ANDs with constants, shifts; they can then be be propagated by logical operations, shifts, sign-extensions, negations, deposit operations, and conditional moves. Other operations will just reset the mask to all-ones, i.e. unknown. [rth: s/target_ulong/tcg_target_ulong/] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Richard Henderson <rth@twiddle.net> Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2013-01-19optimize: only write to state when clearing optimizer dataPaolo Bonzini
The next patch will add to the TCG optimizer a field that should be non-zero in the default case. Thus, replace the memset of the temps array with a loop. Only the state field has to be up-to-date, because others are not used except if the state is TCG_TEMP_COPY or TCG_TEMP_CONST. [rth: Extracted the loop to a function.] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Richard Henderson <rth@twiddle.net> Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2012-11-17TCG: Use gen_opc_buf from context instead of global variable.Evgeny Voevodin
Signed-off-by: Evgeny Voevodin <e.voevodin@samsung.com> Reviewed-by: Richard Henderson <rth@twiddle.net> Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2012-10-28tcg: rework TCG helper flagsAurelien Jarno
The current helper flags, TCG_CALL_CONST and TCG_CALL_PURE might be confusing and doesn't provide enough granularity for some helpers (FP helpers for example). This patch changes them into the following helpers flags: - TCG_CALL_NO_READ_GLOBALS means that the helper does not read globals, either directly or via an exception. They will not be saved to their canonical location before calling the helper. - TCG_CALL_NO_WRITE_GLOBALS means that the helper does not modify any globals. They will only be saved to their canonical locations before calling helpers, but they won't be reloaded afterwise. - TCG_CALL_NO_SIDE_EFFECTS means that the call to the function is removed if the return value is not used. It provides convenience flags, to avoid helper definitions longer than 80 characters. It also provides compatibility flags, and updates the documentation. Reviewed-by: Richard Henderson <rth@twiddle.net> Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2012-10-17tcg: Optimize mulu2Richard Henderson
Like add2, do operand ordering, constant folding, and dead operand elimination. The latter happens about 15% of all mulu2 during an x86_64 bios boot. Signed-off-by: Richard Henderson <rth@twiddle.net> Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>