[NFC] Show instcombine powi simplifications drop FMF.

[vdmitrie]

Summary

Update test for upcoming change.

[spatel]

Use something other than fast on the 2nd call to provide better test coverage.
Please update the CHECK lines with utils/update_test_checks.py (use "--function=powi" if you want to avoid diffs on other functions).

[spatel]

Thanks - LGTM.

llvm/test/Transforms/InstCombine/intrinsics.ll

-; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --function powi
 ; RUN: opt -instcombine -S < %s | FileCheck %s
 
 declare double @llvm.powi.f64(double, i32) nounwind readonly
 declare i32 @llvm.cttz.i32(i32, i1) nounwind readnone
 declare i32 @llvm.ctlz.i32(i32, i1) nounwind readnone
 declare i1 @llvm.cttz.i1(i1, i1) nounwind readnone
 declare i1 @llvm.ctlz.i1(i1, i1) nounwind readnone
 declare i32 @llvm.ctpop.i32(i32) nounwind readnone
 declare <2 x i32> @llvm.cttz.v2i32(<2 x i32>, i1) nounwind readnone
 declare <2 x i32> @llvm.ctlz.v2i32(<2 x i32>, i1) nounwind readnone
 declare <2 x i32> @llvm.ctpop.v2i32(<2 x i32>) nounwind readnone
 declare i8 @llvm.ctlz.i8(i8, i1) nounwind readnone
 declare <2 x i8> @llvm.ctlz.v2i8(<2 x i8>, i1) nounwind readnone
 declare double @llvm.cos.f64(double %Val) nounwind readonly
 declare double @llvm.sin.f64(double %Val) nounwind readonly
 declare double @llvm.floor.f64(double %Val) nounwind readonly
 declare double @llvm.ceil.f64(double %Val) nounwind readonly
 declare double @llvm.trunc.f64(double %Val) nounwind readonly
 declare double @llvm.rint.f64(double %Val) nounwind readonly
 declare double @llvm.nearbyint.f64(double %Val) nounwind readonly
 
 define void @powi(double %V, double *%P) {
-  %A = tail call double @llvm.powi.f64(double %V, i32 -1) nounwind
+; CHECK-LABEL: @powi(
+; CHECK-NEXT:    [[A:%.*]] = fdiv double 1.000000e+00, [[V:%.*]]
+; CHECK-NEXT:    store volatile double [[A]], double* [[P:%.*]], align 8
+; CHECK-NEXT:    [[D:%.*]] = fmul double [[V]], [[V]]
+; CHECK-NEXT:    store volatile double [[D]], double* [[P]], align 8
+; CHECK-NEXT:    ret void
+;
+  %A = tail call fast double @llvm.powi.f64(double %V, i32 -1) nounwind
   store volatile double %A, double* %P
 
-  %D = tail call double @llvm.powi.f64(double %V, i32 2) nounwind
+  %D = tail call nnan double @llvm.powi.f64(double %V, i32 2) nounwind
   store volatile double %D, double* %P
   ret void
-; CHECK-LABEL: @powi(
-; CHECK: %A = fdiv double 1.0{{.*}}, %V
-; CHECK: store volatile double %A,
-; CHECK: %D = fmul double %V, %V
-; CHECK: store volatile double %D
 }
 
 define i32 @cttz(i32 %a) {
 ; CHECK-LABEL: @cttz(
 ; CHECK-NEXT:    ret i32 3
 ;
   %or = or i32 %a, 8
   %and = and i32 %or, -8