[InstCombine] Only preserve the flags from rhs when the and is not logical

Author: XChy

llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp

@@ -1444,8 +1444,10 @@ Value *InstCombinerImpl::foldLogicOfFCmps(FCmpInst *LHS, FCmpInst *RHS,
     }
     if (IsLessThanOrLessEqual(IsAnd ? PredL : PredR)) {
       BuilderTy::FastMathFlagGuard Guard(Builder);
-      Builder.setFastMathFlags(LHS->getFastMathFlags() |
-                               RHS->getFastMathFlags());
+      FastMathFlags NewFlag = LHS->getFastMathFlags();
+      if (!IsLogicalSelect)
+        NewFlag |= RHS->getFastMathFlags();
+      Builder.setFastMathFlags(NewFlag);
 
       Value *FAbs = Builder.CreateUnaryIntrinsic(Intrinsic::fabs, LHS0);
       return Builder.CreateFCmp(PredL, FAbs,

llvm/test/Transforms/InstCombine/fcmp-range-check-idiom.ll

@@ -363,8 +363,8 @@ define i1 @test_and_olt_fmf_propagation_union(float %x) {
 define i1 @test_and_olt_fmf_propagation_union_logical_rhs_poison(float %x) {
 ; CHECK-LABEL: define i1 @test_and_olt_fmf_propagation_union_logical_rhs_poison(
 ; CHECK-SAME: float [[X:%.*]]) {
-; CHECK-NEXT:    [[TMP1:%.*]] = call ninf float @llvm.fabs.f32(float [[X]])
-; CHECK-NEXT:    [[COND:%.*]] = fcmp ninf olt float [[TMP1]], 0x3C00000000000000
+; CHECK-NEXT:    [[TMP1:%.*]] = call float @llvm.fabs.f32(float [[X]])
+; CHECK-NEXT:    [[COND:%.*]] = fcmp olt float [[TMP1]], 0x3C00000000000000
 ; CHECK-NEXT:    ret i1 [[COND]]
 ;
   %cmp1 = fcmp ninf olt float %x, 0x3C00000000000000