1 ; RUN: opt -S -instcombine -o - %s | FileCheck %s 2 3 ; Test that fast math lib call simplification of double math function to float 4 ; equivalent doesn't occur when the calling function matches the float 5 ; equivalent math function. Otherwise this can cause the generation of infinite 6 ; loops when compiled with -O2/3 and fast math. 7 8 ; Test case C source: 9 ; 10 ; extern double exp(double x); 11 ; inline float expf(float x) { return (float) exp((double) x); } 12 ; float fn(float f) { return expf(f); } 13 ; 14 ; IR generated with command: 15 ; 16 ; clang -cc1 -O2 -ffast-math -emit-llvm -disable-llvm-passes -triple x86_64-unknown-unknown -o - <srcfile> 17 18 target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128" 19 target triple = "x86_64-unknown-unknown" 20 21 ; Function Attrs: nounwind 22 define float @fn(float %f) #0 { 23 ; CHECK: define float @fn( 24 ; CHECK: call fast float @expf( 25 %f.addr = alloca float, align 4 26 store float %f, float* %f.addr, align 4, !tbaa !1 27 %1 = load float, float* %f.addr, align 4, !tbaa !1 28 %call = call fast float @expf(float %1) #3 29 ret float %call 30 } 31 32 ; Function Attrs: inlinehint nounwind readnone 33 define available_externally float @expf(float %x) #1 { 34 ; CHECK: define available_externally float @expf( 35 ; CHECK: fpext float 36 ; CHECK: call fast double @exp( 37 ; CHECK: fptrunc double 38 %x.addr = alloca float, align 4 39 store float %x, float* %x.addr, align 4, !tbaa !1 40 %1 = load float, float* %x.addr, align 4, !tbaa !1 41 %conv = fpext float %1 to double 42 %call = call fast double @exp(double %conv) #3 43 %conv1 = fptrunc double %call to float 44 ret float %conv1 45 } 46 47 ; Function Attrs: nounwind readnone 48 declare double @exp(double) #2 49 50 attributes #0 = { nounwind "correctly-rounded-divide-sqrt-fp-math"="false" "disable-tail-calls"="false" "less-precise-fpmad"="false" "no-frame-pointer-elim"="false" "no-infs-fp-math"="false" "no-jump-tables"="false" "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" "no-trapping-math"="false" "stack-protector-buffer-size"="8" "target-features"="+mmx,+sse,+sse2,+x87" "unsafe-fp-math"="false" "use-soft-float"="false" } 51 attributes #1 = { inlinehint nounwind readnone "correctly-rounded-divide-sqrt-fp-math"="false" "disable-tail-calls"="false" "less-precise-fpmad"="false" "no-frame-pointer-elim"="false" "no-infs-fp-math"="false" "no-jump-tables"="false" "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" "no-trapping-math"="false" "stack-protector-buffer-size"="8" "target-features"="+mmx,+sse,+sse2,+x87" "unsafe-fp-math"="false" "use-soft-float"="false" } 52 attributes #2 = { nounwind readnone } 53 54 !llvm.ident = !{!0} 55 56 !0 = !{!"clang version 5.0.0"} 57 !1 = !{!2, !2, i64 0} 58 !2 = !{!"float", !3, i64 0} 59 !3 = !{!"omnipotent char", !4, i64 0} 60 !4 = !{!"Simple C/C++ TBAA"} 61
