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tcg/optimize: Fix folding of vector bitsel

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It looks like a typo. When the false value (C) is the constant -1, the
correct fold should be: R = B | ~A

Reproducer (LoongArch64 assembly):

     .text
     .globl  _start
 _start:
     vldi    $vr1, 3073
     vldi    $vr2, 1023
     vbitsel.v       $vr0, $vr2, $vr1, $vr2
     vpickve2gr.d    $a1, $vr0, 1
     xori    $a0, $a1, 1
     li.w    $a7, 93
     syscall 0

Fixes: e58b977238 ("tcg/optimize: Optimize bitsel_vec")
Link: https://github.com/llvm/llvm-project/issues/159610
Signed-off-by: WANG Rui <wangrui@loongson.cn>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-ID: <20250919124901.2756538-1-wangrui@loongson.cn>
This commit is contained in:
WANG Rui 2025-09-19 20:49:01 +08:00 • committed by Richard Henderson
parent 76d2b8d42a
commit a50347a414
1 changed files with 2 additions and 1 deletions
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3
tcg/optimize.c
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@ -1568,9 +1568,10 @@ static bool fold_bitsel_vec(OptContext *ctx, TCGOp *op)
return fold_and(ctx, op);
}
if (fv == -1 && TCG_TARGET_HAS_orc_vec) {
TCGArg ta = op->args[2];
op->opc = INDEX_op_orc_vec;
op->args[2] = op->args[1];
op->args[1] = op->args[3];
op->args[1] = ta;
return fold_orc(ctx, op);
}
}