[llvm] [InstCombine] Fix flag propagation in `foldSelectIntoOp` (PR #162003)

[Yingwei Zheng via llvm-commits]

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@@ -23,6 +23,50 @@ define float @select_fpclass_fadd(i1 %cond, float nofpclass(nan) %A, float %B) {
   ret float %D
 }
 
+define float @select_fpclass_fadd_ninf1(i1 %cond, float nofpclass(nan) %A, float %B) {
+; CHECK-LABEL: @select_fpclass_fadd_ninf1(
+; CHECK-NEXT:    [[C:%.*]] = select i1 [[COND:%.*]], float [[B:%.*]], float -0.000000e+00
+; CHECK-NEXT:    [[D:%.*]] = fadd float [[A:%.*]], [[C]]
+; CHECK-NEXT:    ret float [[D]]
+;
+  %C = fadd ninf float %A, %B
+  %D = select i1 %cond, float %C, float %A
+  ret float %D
+}
+
+define float @select_fpclass_fadd_ninf2(i1 %cond, float nofpclass(nan) %A, float %B) {
+; CHECK-LABEL: @select_fpclass_fadd_ninf2(
+; CHECK-NEXT:    [[C:%.*]] = select i1 [[COND:%.*]], float [[B:%.*]], float -0.000000e+00
+; CHECK-NEXT:    [[D:%.*]] = fadd float [[A:%.*]], [[C]]
+; CHECK-NEXT:    ret float [[D]]
+;
+  %C = fadd float %A, %B
+  %D = select ninf i1 %cond, float %C, float %A
+  ret float %D
+}
+
+define float @select_fpclass_fadd_ninf3(i1 %cond, float nofpclass(nan) %A, float %B) {
+; CHECK-LABEL: @select_fpclass_fadd_ninf3(
+; CHECK-NEXT:    [[C:%.*]] = select ninf i1 [[COND:%.*]], float [[B:%.*]], float -0.000000e+00
+; CHECK-NEXT:    [[D:%.*]] = fadd ninf float [[A:%.*]], [[C]]
+; CHECK-NEXT:    ret float [[D]]
+;
+  %C = fadd ninf float %A, %B
+  %D = select ninf i1 %cond, float %C, float %A
+  ret float %D
+}
+
+define float @select_fpclass_fadd_nnan_ninf(i1 %cond, float nofpclass(nan) %A, float %B) {
+; CHECK-LABEL: @select_fpclass_fadd_nnan_ninf(
+; CHECK-NEXT:    [[C:%.*]] = select nnan ninf i1 [[COND:%.*]], float [[B:%.*]], float -0.000000e+00
+; CHECK-NEXT:    [[D:%.*]] = fadd float [[A:%.*]], [[C]]
+; CHECK-NEXT:    ret float [[D]]
+;
+  %C = fadd float %A, %B
+  %D = select nnan ninf i1 %cond, float %C, float %A
+  ret float %D
+}
+
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dtcxzyw wrote:

Done.

https://github.com/llvm/llvm-project/pull/162003