Index: llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp
===================================================================
--- llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp
+++ llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp
@@ -2303,6 +2303,21 @@
       }
     }
 
+    // If there are no NaNs, convert minnum/maxnum to fcmp/select for better
+    // analysis.
+    if (II->hasNoNaNs() &&
+        (IID == Intrinsic::minnum || IID == Intrinsic::maxnum)) {
+      // Minnum/maxnum have unspecified behavior comparing (+/-)0.0, so set nsz.
+      BuilderTy::FastMathFlagGuard Guard(Builder);
+      FastMathFlags FMF = II->getFastMathFlags();
+      FMF.setNoSignedZeros();
+      Builder.setFastMathFlags(FMF);
+      FCmpInst::Predicate Pred = IID == Intrinsic::maxnum ? FCmpInst::FCMP_OGT
+                                                          : FCmpInst::FCMP_OLT;
+      Value *Cmp = Builder.CreateFCmp(Pred, Arg0, Arg1);
+      return SelectInst::Create(Cmp, Arg0, Arg1);
+    }
+
     break;
   }
   case Intrinsic::fmuladd: {
Index: llvm/test/Transforms/InstCombine/AMDGPU/amdgcn-intrinsics.ll
===================================================================
--- llvm/test/Transforms/InstCombine/AMDGPU/amdgcn-intrinsics.ll
+++ llvm/test/Transforms/InstCombine/AMDGPU/amdgcn-intrinsics.ll
@@ -1413,7 +1413,8 @@
 
 define float @fmed3_fmf_undef_x_y_f32(float %x, float %y) {
 ; CHECK-LABEL: @fmed3_fmf_undef_x_y_f32(
-; CHECK-NEXT:    [[MED3:%.*]] = call nnan float @llvm.minnum.f32(float [[X:%.*]], float [[Y:%.*]])
+; CHECK-NEXT:    [[TMP1:%.*]] = fcmp nnan nsz olt float [[X:%.*]], [[Y:%.*]]
+; CHECK-NEXT:    [[MED3:%.*]] = select i1 [[TMP1]], float [[X]], float [[Y]]
 ; CHECK-NEXT:    ret float [[MED3]]
 ;
   %med3 = call nnan float @llvm.amdgcn.fmed3.f32(float undef, float %x, float %y)
@@ -2452,4 +2453,3 @@
 }
 
 ; CHECK: attributes #5 = { convergent }
-
Index: llvm/test/Transforms/InstCombine/maxnum.ll
===================================================================
--- llvm/test/Transforms/InstCombine/maxnum.ll
+++ llvm/test/Transforms/InstCombine/maxnum.ll
@@ -157,8 +157,9 @@
 
 define float @maxnum_f32_1_maxnum_p0_val_fast(float %x) {
 ; CHECK-LABEL: @maxnum_f32_1_maxnum_p0_val_fast(
-; CHECK-NEXT:    [[TMP1:%.*]] = call fast float @llvm.maxnum.f32(float [[X:%.*]], float 1.000000e+00)
-; CHECK-NEXT:    ret float [[TMP1]]
+; CHECK-NEXT:    [[TMP1:%.*]] = fcmp fast ogt float [[X:%.*]], 1.000000e+00
+; CHECK-NEXT:    [[TMP2:%.*]] = select i1 [[TMP1]], float [[X]], float 1.000000e+00
+; CHECK-NEXT:    ret float [[TMP2]]
 ;
   %y = call float @llvm.maxnum.f32(float 0.0, float %x)
   %z = call fast float @llvm.maxnum.f32(float %y, float 1.0)
@@ -167,8 +168,9 @@
 
 define float @maxnum_f32_1_maxnum_p0_val_nnan_ninf(float %x) {
 ; CHECK-LABEL: @maxnum_f32_1_maxnum_p0_val_nnan_ninf(
-; CHECK-NEXT:    [[TMP1:%.*]] = call nnan ninf float @llvm.maxnum.f32(float [[X:%.*]], float 1.000000e+00)
-; CHECK-NEXT:    ret float [[TMP1]]
+; CHECK-NEXT:    [[TMP1:%.*]] = fcmp nnan ninf nsz ogt float [[X:%.*]], 1.000000e+00
+; CHECK-NEXT:    [[TMP2:%.*]] = select i1 [[TMP1]], float [[X]], float 1.000000e+00
+; CHECK-NEXT:    ret float [[TMP2]]
 ;
   %y = call float @llvm.maxnum.f32(float 0.0, float %x)
   %z = call nnan ninf float @llvm.maxnum.f32(float %y, float 1.0)
@@ -236,8 +238,9 @@
 
 define float @neg_neg_vec_fmf(float %x, float %y) {
 ; CHECK-LABEL: @neg_neg_vec_fmf(
-; CHECK-NEXT:    [[TMP1:%.*]] = call fast float @llvm.minnum.f32(float [[X:%.*]], float [[Y:%.*]])
-; CHECK-NEXT:    [[R:%.*]] = fsub fast float -0.000000e+00, [[TMP1]]
+; CHECK-NEXT:    [[TMP1:%.*]] = fcmp fast olt float [[X:%.*]], [[Y:%.*]]
+; CHECK-NEXT:    [[TMP2:%.*]] = select i1 [[TMP1]], float [[X]], float [[Y]]
+; CHECK-NEXT:    [[R:%.*]] = fsub fast float -0.000000e+00, [[TMP2]]
 ; CHECK-NEXT:    ret float [[R]]
 ;
   %negx = fsub arcp float -0.0, %x
Index: llvm/test/Transforms/InstCombine/minnum.ll
===================================================================
--- llvm/test/Transforms/InstCombine/minnum.ll
+++ llvm/test/Transforms/InstCombine/minnum.ll
@@ -159,8 +159,9 @@
 
 define float @minnum_f32_1_minnum_p0_val_fast(float %x) {
 ; CHECK-LABEL: @minnum_f32_1_minnum_p0_val_fast(
-; CHECK-NEXT:    [[TMP1:%.*]] = call fast float @llvm.minnum.f32(float [[X:%.*]], float 0.000000e+00)
-; CHECK-NEXT:    ret float [[TMP1]]
+; CHECK-NEXT:    [[TMP1:%.*]] = fcmp fast olt float [[X:%.*]], 0.000000e+00
+; CHECK-NEXT:    [[TMP2:%.*]] = select i1 [[TMP1]], float [[X]], float 0.000000e+00
+; CHECK-NEXT:    ret float [[TMP2]]
 ;
   %y = call float @llvm.minnum.f32(float 0.0, float %x)
   %z = call fast float @llvm.minnum.f32(float %y, float 1.0)
@@ -169,8 +170,9 @@
 
 define float @minnum_f32_1_minnum_p0_val_nnan_ninf(float %x) {
 ; CHECK-LABEL: @minnum_f32_1_minnum_p0_val_nnan_ninf(
-; CHECK-NEXT:    [[TMP1:%.*]] = call nnan ninf float @llvm.minnum.f32(float [[X:%.*]], float 0.000000e+00)
-; CHECK-NEXT:    ret float [[TMP1]]
+; CHECK-NEXT:    [[TMP1:%.*]] = fcmp nnan ninf nsz olt float [[X:%.*]], 0.000000e+00
+; CHECK-NEXT:    [[TMP2:%.*]] = select i1 [[TMP1]], float [[X]], float 0.000000e+00
+; CHECK-NEXT:    ret float [[TMP2]]
 ;
   %y = call float @llvm.minnum.f32(float 0.0, float %x)
   %z = call nnan ninf float @llvm.minnum.f32(float %y, float 1.0)
@@ -261,8 +263,9 @@
 
 define <2 x double> @neg_neg_vec_fmf(<2 x double> %x, <2 x double> %y) {
 ; CHECK-LABEL: @neg_neg_vec_fmf(
-; CHECK-NEXT:    [[TMP1:%.*]] = call nnan ninf <2 x double> @llvm.maxnum.v2f64(<2 x double> [[X:%.*]], <2 x double> [[Y:%.*]])
-; CHECK-NEXT:    [[R:%.*]] = fsub nnan ninf <2 x double> <double -0.000000e+00, double -0.000000e+00>, [[TMP1]]
+; CHECK-NEXT:    [[TMP1:%.*]] = fcmp nnan ninf nsz ogt <2 x double> [[X:%.*]], [[Y:%.*]]
+; CHECK-NEXT:    [[TMP2:%.*]] = select <2 x i1> [[TMP1]], <2 x double> [[X]], <2 x double> [[Y]]
+; CHECK-NEXT:    [[R:%.*]] = fsub nnan ninf <2 x double> <double -0.000000e+00, double -0.000000e+00>, [[TMP2]]
 ; CHECK-NEXT:    ret <2 x double> [[R]]
 ;
   %negx = fsub reassoc <2 x double> <double -0.0, double -0.0>, %x