ValueTracking: Recognize fcmp ole/ugt with inf as a class test (#79095)

These were missed and hopefully avoids assertions when
dc3faf0ed0e3f1ea9e435a006167d9649f865da1 is recommitted.

4 files changed, 35 insertions, 24 deletions

diff --git a/llvm/lib/Analysis/ValueTracking.cpp b/llvm/lib/Analysis/ValueTracking.cpp
index 34d5010..5d6c346 100644
--- a/llvm/lib/Analysis/ValueTracking.cpp
+++ b/llvm/lib/Analysis/ValueTracking.cpp
@@ -4065,7 +4065,7 @@ llvm::fcmpToClassTest(FCmpInst::Predicate Pred, const Function &F, Value *LHS,
     case FCmpInst::FCMP_ULE: // isnan(x) || x <= 0
       return {LHS, fcNegative | fcPosZero | fcNan};
     default:
-      break;
+      llvm_unreachable("all compare types are handled");
     }
 
     return {nullptr, fcAllFlags};
@@ -4184,8 +4184,22 @@ llvm::fcmpToClassTest(FCmpInst::Predicate Pred, const Function &F, Value *LHS,
       Mask = fcNone;
       break;
     }
+    case FCmpInst::FCMP_OLE:
+    case FCmpInst::FCMP_UGT: {
+      if (ConstRHS->isNegative()) {
+        Mask = IsFabs ? fcNone : fcNegInf;
+        break;
+      }
+
+      // fcmp ole x, +inf -> fcmp ord x, x
+      // fcmp ole fabs(x), +inf -> fcmp ord x, x
+      // fcmp ole x, -inf -> fcmp oeq x, -inf
+      // fcmp ole fabs(x), -inf -> false
+      Mask = ~fcNan;
+      break;
+    }
     default:
-      return {nullptr, fcAllFlags};
+      llvm_unreachable("all compare types are handled");
     }
   } else if (ConstRHS->isSmallestNormalized() && !ConstRHS->isNegative()) {
     // Match pattern that's used in __builtin_isnormal.
diff --git a/llvm/test/Transforms/Attributor/nofpclass-implied-by-fcmp.ll b/llvm/test/Transforms/Attributor/nofpclass-implied-by-fcmp.ll
index ccd01de..d34e8ad 100644
--- a/llvm/test/Transforms/Attributor/nofpclass-implied-by-fcmp.ll
+++ b/llvm/test/Transforms/Attributor/nofpclass-implied-by-fcmp.ll
@@ -2400,8 +2400,8 @@ define float @assume_oeq_smallest_normal_known_pos(float nofpclass(ninf nsub nno
 ;---------------------------------------------------------------------
 
 define float @assume_ole_pinf(float %arg) {
-; CHECK-LABEL: define float @assume_ole_pinf(
-; CHECK-SAME: float returned [[ARG:%.*]]) #[[ATTR3]] {
+; CHECK-LABEL: define nofpclass(nan) float @assume_ole_pinf(
+; CHECK-SAME: float returned nofpclass(nan) [[ARG:%.*]]) #[[ATTR3]] {
 ; CHECK-NEXT:    [[FCMP:%.*]] = fcmp ole float [[ARG]], 0x7FF0000000000000
 ; CHECK-NEXT:    call void @llvm.assume(i1 noundef [[FCMP]]) #[[ATTR5]]
 ; CHECK-NEXT:    ret float [[ARG]]
@@ -2412,8 +2412,8 @@ define float @assume_ole_pinf(float %arg) {
 }
 
 define float @assume_ole_ninf(float %arg) {
-; CHECK-LABEL: define float @assume_ole_ninf(
-; CHECK-SAME: float returned [[ARG:%.*]]) #[[ATTR3]] {
+; CHECK-LABEL: define nofpclass(nan pinf zero sub norm) float @assume_ole_ninf(
+; CHECK-SAME: float returned nofpclass(nan pinf zero sub norm) [[ARG:%.*]]) #[[ATTR3]] {
 ; CHECK-NEXT:    [[FCMP:%.*]] = fcmp ole float [[ARG]], 0xFFF0000000000000
 ; CHECK-NEXT:    call void @llvm.assume(i1 noundef [[FCMP]]) #[[ATTR5]]
 ; CHECK-NEXT:    ret float [[ARG]]
@@ -2424,8 +2424,8 @@ define float @assume_ole_ninf(float %arg) {
 }
 
 define float @assume_ugt_pinf(float %arg) {
-; CHECK-LABEL: define float @assume_ugt_pinf(
-; CHECK-SAME: float returned [[ARG:%.*]]) #[[ATTR3]] {
+; CHECK-LABEL: define nofpclass(inf zero sub norm) float @assume_ugt_pinf(
+; CHECK-SAME: float returned nofpclass(inf zero sub norm) [[ARG:%.*]]) #[[ATTR3]] {
 ; CHECK-NEXT:    [[FCMP:%.*]] = fcmp ugt float [[ARG]], 0x7FF0000000000000
 ; CHECK-NEXT:    call void @llvm.assume(i1 noundef [[FCMP]]) #[[ATTR5]]
 ; CHECK-NEXT:    ret float [[ARG]]
@@ -2436,8 +2436,8 @@ define float @assume_ugt_pinf(float %arg) {
 }
 
 define float @assume_ugt_ninf(float %arg) {
-; CHECK-LABEL: define float @assume_ugt_ninf(
-; CHECK-SAME: float returned [[ARG:%.*]]) #[[ATTR3]] {
+; CHECK-LABEL: define nofpclass(ninf) float @assume_ugt_ninf(
+; CHECK-SAME: float returned nofpclass(ninf) [[ARG:%.*]]) #[[ATTR3]] {
 ; CHECK-NEXT:    [[FCMP:%.*]] = fcmp ugt float [[ARG]], 0xFFF0000000000000
 ; CHECK-NEXT:    call void @llvm.assume(i1 noundef [[FCMP]]) #[[ATTR5]]
 ; CHECK-NEXT:    ret float [[ARG]]
@@ -2448,8 +2448,8 @@ define float @assume_ugt_ninf(float %arg) {
 }
 
 define float @assume_fabs_ole_pinf(float %arg) {
-; CHECK-LABEL: define nofpclass(ninf nzero nsub nnorm) float @assume_fabs_ole_pinf(
-; CHECK-SAME: float returned nofpclass(ninf nzero nsub nnorm) [[ARG:%.*]]) #[[ATTR3]] {
+; CHECK-LABEL: define nofpclass(nan ninf nzero nsub nnorm) float @assume_fabs_ole_pinf(
+; CHECK-SAME: float returned nofpclass(nan ninf nzero nsub nnorm) [[ARG:%.*]]) #[[ATTR3]] {
 ; CHECK-NEXT:    [[FABS:%.*]] = call float @llvm.fabs.f32(float [[ARG]]) #[[ATTR4]]
 ; CHECK-NEXT:    [[FCMP:%.*]] = fcmp ole float [[FABS]], 0x7FF0000000000000
 ; CHECK-NEXT:    call void @llvm.assume(i1 noundef [[FCMP]]) #[[ATTR5]]
@@ -2462,8 +2462,8 @@ define float @assume_fabs_ole_pinf(float %arg) {
 }
 
 define float @assume_fabs_ole_ninf(float %arg) {
-; CHECK-LABEL: define nofpclass(ninf nzero nsub nnorm) float @assume_fabs_ole_ninf(
-; CHECK-SAME: float returned nofpclass(ninf nzero nsub nnorm) [[ARG:%.*]]) #[[ATTR3]] {
+; CHECK-LABEL: define nofpclass(all) float @assume_fabs_ole_ninf(
+; CHECK-SAME: float returned nofpclass(all) [[ARG:%.*]]) #[[ATTR3]] {
 ; CHECK-NEXT:    call void @llvm.assume(i1 noundef false) #[[ATTR5]]
 ; CHECK-NEXT:    ret float [[ARG]]
 ;
@@ -2474,8 +2474,8 @@ define float @assume_fabs_ole_ninf(float %arg) {
 }
 
 define float @assume_fabs_ugt_pinf(float %arg) {
-; CHECK-LABEL: define nofpclass(ninf nzero nsub nnorm) float @assume_fabs_ugt_pinf(
-; CHECK-SAME: float returned nofpclass(ninf nzero nsub nnorm) [[ARG:%.*]]) #[[ATTR3]] {
+; CHECK-LABEL: define nofpclass(inf zero sub norm) float @assume_fabs_ugt_pinf(
+; CHECK-SAME: float returned nofpclass(inf zero sub norm) [[ARG:%.*]]) #[[ATTR3]] {
 ; CHECK-NEXT:    [[FABS:%.*]] = call float @llvm.fabs.f32(float [[ARG]]) #[[ATTR4]]
 ; CHECK-NEXT:    [[FCMP:%.*]] = fcmp ugt float [[FABS]], 0x7FF0000000000000
 ; CHECK-NEXT:    call void @llvm.assume(i1 noundef [[FCMP]]) #[[ATTR5]]
diff --git a/llvm/test/Transforms/InstCombine/and-fcmp.ll b/llvm/test/Transforms/InstCombine/and-fcmp.ll
index 90d3417..42e3f34 100644
--- a/llvm/test/Transforms/InstCombine/and-fcmp.ll
+++ b/llvm/test/Transforms/InstCombine/and-fcmp.ll
@@ -4820,10 +4820,7 @@ define i1 @clang_builtin_isnormal_inf_check_olt(half %x) {
 
 define i1 @clang_builtin_isnormal_inf_check_ole(half %x) {
 ; CHECK-LABEL: @clang_builtin_isnormal_inf_check_ole(
-; CHECK-NEXT:    [[FABS_X:%.*]] = call half @llvm.fabs.f16(half [[X:%.*]])
-; CHECK-NEXT:    [[ORD:%.*]] = fcmp ord half [[X]], 0xH0000
-; CHECK-NEXT:    [[CMP:%.*]] = fcmp ole half [[FABS_X]], 0xH7C00
-; CHECK-NEXT:    [[AND:%.*]] = and i1 [[ORD]], [[CMP]]
+; CHECK-NEXT:    [[AND:%.*]] = fcmp ord half [[X:%.*]], 0xH0000
 ; CHECK-NEXT:    ret i1 [[AND]]
 ;
   %fabs.x = call half @llvm.fabs.f16(half %x)
diff --git a/llvm/unittests/Analysis/ValueTrackingTest.cpp b/llvm/unittests/Analysis/ValueTrackingTest.cpp
index 27f6318..8104a32 100644
--- a/llvm/unittests/Analysis/ValueTrackingTest.cpp
+++ b/llvm/unittests/Analysis/ValueTrackingTest.cpp
@@ -1945,14 +1945,14 @@ TEST_F(ComputeKnownFPClassTest, FCmpToClassTest_PInf) {
   auto [OleVal, OleClass] =
       fcmpToClassTest(CmpInst::FCMP_OLE, *A3->getFunction(), A3->getOperand(0),
                       A3->getOperand(1));
-  EXPECT_EQ(nullptr, OleVal);
-  EXPECT_EQ(fcAllFlags, OleClass);
+  EXPECT_EQ(A->getOperand(0), OleVal);
+  EXPECT_EQ(~fcNan, OleClass);
 
   auto [UgtVal, UgtClass] =
       fcmpToClassTest(CmpInst::FCMP_UGT, *A4->getFunction(), A4->getOperand(0),
                       A4->getOperand(1));
-  EXPECT_EQ(nullptr, UgtVal);
-  EXPECT_EQ(fcAllFlags, UgtClass);
+  EXPECT_EQ(A4->getOperand(0), UgtVal);
+  EXPECT_EQ(fcNan, UgtClass);
 }
 
 TEST_F(ComputeKnownFPClassTest, SqrtNszSignBit) {