[llvm] [FPEnv][AMDGPU] Correct AMDGPUSimplifyLibCalls handling of strictfp attribute. (PR #86705)

[Kevin P. Neal via llvm-commits]

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@@ -820,11 +820,11 @@ define float @test_pown_fast_f32_strictfp(float %x, i32 %y) #1 {
 ; CHECK-LABEL: define float @test_pown_fast_f32_strictfp
 ; CHECK-SAME: (float [[X:%.*]], i32 [[Y:%.*]]) #[[ATTR0:[0-9]+]] {
 ; CHECK-NEXT:  entry:
-; CHECK-NEXT:    [[__FABS:%.*]] = call fast float @llvm.fabs.f32(float [[X]])
-; CHECK-NEXT:    [[__LOG2:%.*]] = call fast float @llvm.log2.f32(float [[__FABS]])
-; CHECK-NEXT:    [[POWNI2F:%.*]] = sitofp i32 [[Y]] to float
-; CHECK-NEXT:    [[__YLOGX:%.*]] = fmul fast float [[__LOG2]], [[POWNI2F]]
-; CHECK-NEXT:    [[__EXP2:%.*]] = call fast float @llvm.exp2.f32(float [[__YLOGX]])
+; CHECK-NEXT:    [[__FABS:%.*]] = call fast float @llvm.fabs.f32(float [[X]]) #[[ATTR0]]
+; CHECK-NEXT:    [[__LOG2:%.*]] = call fast float @llvm.log2.f32(float [[__FABS]]) #[[ATTR0]]
+; CHECK-NEXT:    [[POWNI2F:%.*]] = call fast float @llvm.experimental.constrained.sitofp.f32.i32(i32 [[Y]], metadata !"round.dynamic", metadata !"fpexcept.strict") #[[ATTR0]]
+; CHECK-NEXT:    [[__YLOGX:%.*]] = call fast float @llvm.experimental.constrained.fmul.f32(float [[POWNI2F]], float [[__LOG2]], metadata !"round.dynamic", metadata !"fpexcept.strict") #[[ATTR0]]
+; CHECK-NEXT:    [[__EXP2:%.*]] = call fast float @llvm.exp2.f32(float [[__YLOGX]]) #[[ATTR0]]
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kpneal wrote:

The way to fix those would be to add code to the IRBuilder in CreateCall to check for strictfp mode and switch over to the constrained call. That code hasn't been written yet. Is that something I need to do before I can move forward here?

https://github.com/llvm/llvm-project/pull/86705