[llvm] Optimize fptrunc(x)>=C1 --> x>=C2 (PR #99475)

[via llvm-commits]

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@@ -0,0 +1,11 @@
+; RUN: opt -passes=instcombine -S < %s | FileCheck %s
+
+
+;CHECK-LABEL: @src(
+;CHECK: %result = fcmp oge double %0, 1.000000e+02
+;CHECK-NEXT: ret i1 %result
+define i1 @src(double %0) {
+    %trunc = fptrunc double %0 to float
+    %result = fcmp oge float %trunc, 1.000000e+02
+    ret i1 %result
+}
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kissholic wrote:

> Test more combinations of types, including vectors. Also test flag preservation behavior
@arsenm Sorry, could you give me a hint what 'flag preservation behavior' means in IR?

https://github.com/llvm/llvm-project/pull/99475