b326d4ff94
This reverts partial of a2fb5446 (actually, 2508ef01) about removing negated FP constant immediately if it has no uses. However, as discussed in bug 47517, there're cases when NegX is folded into constant from other places while NegY is removed by that line of code and NegX is equal to NegY. In these cases, NegX is deleted before used and crash happens. So revert the code and add necessary test case.
42 lines
1.4 KiB
LLVM
42 lines
1.4 KiB
LLVM
; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
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; RUN: llc -mtriple x86_64 < %s | FileCheck %s
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; To ensure unused floating point constant is correctly removed
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define float @test(float %src, float* %p) {
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; CHECK-LABEL: test:
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; CHECK: # %bb.0: # %entry
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; CHECK-NEXT: movq $0, (%rdi)
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; CHECK-NEXT: xorps %xmm0, %xmm0
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; CHECK-NEXT: retq
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entry:
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%a0 = getelementptr inbounds float, float* %p, i32 0
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%a1 = getelementptr inbounds float, float* %p, i32 1
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store float 0.000000e+00, float* %a0
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store float 0.000000e+00, float* %a1
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%zero = load float, float* %a0
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%fmul1 = fmul fast float %zero, %src
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%fadd1 = fadd fast float %fmul1, %zero
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%fmul2 = fmul fast float %fadd1, 2.000000e+00
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%fmul3 = fmul fast float %fmul2, %fmul2
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%fmul4 = fmul fast float %fmul2, 2.000000e+00
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%fadd2 = fadd fast float %fmul4, -3.000000e+00
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%fmul5 = fmul fast float %fadd2, %fmul2
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%fadd3 = fadd fast float %fmul2, %src
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%fadd4 = fadd fast float %fadd3, %fmul5
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%fmul6 = fmul fast float %fmul3, %fadd4
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ret float %fmul6
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}
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; To ensure negated result will not be removed when NegX=NegY and
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; NegX is needed
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define float @test2(float %x, float %y) {
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%add = fadd fast float %x, 750.0
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%sub = fsub fast float %x, %add
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%mul = fmul fast float %sub, %sub
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%mul2 = fmul fast float %mul, %sub
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%add2 = fadd fast float %mul2, 1.0
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%add3 = fadd fast float %mul2, %add2
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%mul3 = fmul fast float %y, %add3
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ret float %mul3
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}
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