[llvm-branch-commits] [llvm] ValueTracking: Improve handling for fma/fmuladd (PR #175614)

[Matt Arsenault via llvm-branch-commits]

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@@ -394,39 +394,39 @@ define half @ret_fma_square__no_nan__no_nan_inf_zero(half noundef nofpclass(nan)
 }
 
 define half @ret_fma_square__no_nan_no_inf_no_zero__no_nan_inf_zero(half noundef nofpclass(nan inf zero) %arg0, half nofpclass(nan inf zero) %arg1) {
-; CHECK-LABEL: define nofpclass(nzero) half @ret_fma_square__no_nan_no_inf_no_zero__no_nan_inf_zero
+; CHECK-LABEL: define nofpclass(nan nzero) half @ret_fma_square__no_nan_no_inf_no_zero__no_nan_inf_zero
 ; CHECK-SAME: (half noundef nofpclass(nan inf zero) [[ARG0:%.*]], half nofpclass(nan inf zero) [[ARG1:%.*]]) #[[ATTR1]] {
-; CHECK-NEXT:    [[CALL:%.*]] = call nofpclass(nzero) half @llvm.fma.f16(half noundef nofpclass(nan inf zero) [[ARG0]], half noundef nofpclass(nan inf zero) [[ARG0]], half nofpclass(nan inf zero) [[ARG1]]) #[[ATTR2]]
+; CHECK-NEXT:    [[CALL:%.*]] = call nofpclass(nan nzero) half @llvm.fma.f16(half noundef nofpclass(nan inf zero) [[ARG0]], half noundef nofpclass(nan inf zero) [[ARG0]], half nofpclass(nan inf zero) [[ARG1]]) #[[ATTR2]]
 ; CHECK-NEXT:    ret half [[CALL]]
 ;
   %call = call half @llvm.fma.f16(half %arg0, half %arg0, half %arg1)
   ret half %call
 }
 
 define half @ret_fma_square__no_nan_no_inf_no_zero__no_nan_inf(half noundef nofpclass(nan inf zero) %arg0, half nofpclass(nan inf) %arg1) {
-; CHECK-LABEL: define nofpclass(nzero) half @ret_fma_square__no_nan_no_inf_no_zero__no_nan_inf
+; CHECK-LABEL: define nofpclass(nan nzero) half @ret_fma_square__no_nan_no_inf_no_zero__no_nan_inf
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arsenm wrote:

This case was broken to begin with. I'm quite surprised that the underflowed multiply can return a -0 

https://github.com/llvm/llvm-project/pull/175614