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tcg/optimize: Do use affected bits

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We inadvertently disabled affected bits optimizations on operations
that use fold_masks_zosa.  These happen relatively often in x86 code
for extract/sextract; for example given the following:

   mov %esi, %ebp
   xor $0x1, %ebp

the optimizer is able to simplify the "extract_i64 rbp,tmp0,$0x0,$0x20"
produced by the second instruction to a move.

Cc: qemu-stable@nongnu.org
Fixes: 932522a9dd ("tcg/optimize: Fold and to extract during optimize")
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-ID: <20251223163720.985578-1-pbonzini@redhat.com>
(cherry picked from commit 23b53ec3a8a279cb5acd5e022b464a4272fe9f8c)
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
This commit is contained in:
Paolo Bonzini 2025-12-23 17:37:20 +01:00 • committed by Michael Tokarev
parent b276b2ca22
commit a53ba65fff
1 changed files with 1 additions and 1 deletions
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2
tcg/optimize.c
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@ -1103,7 +1103,7 @@ static bool fold_masks_zosa_int(OptContext *ctx, TCGOp *op,
static bool fold_masks_zosa(OptContext *ctx, TCGOp *op, uint64_t z_mask, static bool fold_masks_zosa(OptContext *ctx, TCGOp *op, uint64_t z_mask,
uint64_t o_mask, int64_t s_mask, uint64_t a_mask) uint64_t o_mask, int64_t s_mask, uint64_t a_mask)
{ {
fold_masks_zosa_int(ctx, op, z_mask, o_mask, s_mask, -1); fold_masks_zosa_int(ctx, op, z_mask, o_mask, s_mask, a_mask);
return true; return true;
} }