[SystemZ] Test for infinity in testFPKind().

[jonpa]

Summary

Recognize builtin_isinf and BIbuiltin_isfinite (and a few other builtin opcodes for finite checks) in testFPKind().

TDC can check for infinity, and for finite with an inversion of the result.

'finite', '__finite', ... seemed to always work as double with extension/trunction from float/long double. I would guess it is expected to handle those as well with TDC, or?

[jonpa]

clang/lib/CodeGen/TargetInfo.cpp

7228

What are these variants all about...?

[thopre]

clang/lib/CodeGen/TargetInfo.cpp

7228

They were introduced in https://reviews.llvm.org/D24483

[uweigand]

clang/lib/CodeGen/TargetInfo.cpp

7228

This "invert" logic doesn't look correct. "isfinite" and "isinf" both need to return false on NaNs. I think you should just drop the invert logic and use a TDC mask of 0xFC0 (zero, normal, or subnormal) to implement "isfinite".

[thopre]

clang/lib/CodeGen/TargetInfo.cpp

7228

My bad, I made the same mistake in https://reviews.llvm.org/D97125. I'll revert for now and will notify this review once I've got it fixed.

[thopre]

clang/lib/CodeGen/TargetInfo.cpp

7228

I've fixed https://reviews.llvm.org/D97125 and added some isfinite cases.. Thanks @uweigand for pointing the NaN case.

[jonpa]

This "invert" logic doesn't look correct. "isfinite" and "isinf" both need to return false on NaNs. I think you should just drop the invert logic and use a TDC mask of 0xFC0 (zero, normal, or subnormal) to implement "isfinite".

Rebased and updated per review.

[uweigand]

LGTM, thanks!

clang/lib/CodeGen/TargetInfo.cpp

if (Ty->isFloatTy() || Ty->isDoubleTy() || Ty->isFP128Ty()) {
       auto &Ctx = M.getContext();
       llvm::Function *TDCFunc =
           llvm::Intrinsic::getDeclaration(&M, llvm::Intrinsic::s390_tdc, Ty);
       unsigned TDCBits = 0;
       switch (BuiltinID) {
       case Builtin::BI__builtin_isnan:
         TDCBits = 0xf;
         break;
+      case Builtin::BIfinite:
+      case Builtin::BI__finite:
+      case Builtin::BIfinitef:
+      case Builtin::BI__finitef:
+      case Builtin::BIfinitel:
+      case Builtin::BI__finitel:
+      case Builtin::BI__builtin_isfinite:
+        TDCBits = 0xfc0;
+        break;
+      case Builtin::BI__builtin_isinf:
+        TDCBits = 0x30;
+        break;
       default:
         break;
       }
       if (TDCBits)
         return Builder.CreateCall(
             TDCFunc,
             {V, llvm::ConstantInt::get(llvm::Type::getInt64Ty(Ctx), TDCBits)});
     }

clang/test/CodeGen/SystemZ/strictfp_builtins.c

 // NOTE: Assertions have been autogenerated by utils/update_cc_test_checks.py
 // REQUIRES: systemz-registered-target
 // RUN: %clang_cc1 %s -emit-llvm -ffp-exception-behavior=maytrap -o - -triple s390x-linux-gnu | FileCheck %s
 
 #pragma float_control(except, on)
 
 // CHECK-LABEL: @test_isnan_float(
 // CHECK-NEXT:  entry:
 // CHECK-NEXT:    [[F_ADDR:%.*]] = alloca float, align 4
 // CHECK-NEXT:    store float [[F:%.*]], float* [[F_ADDR]], align 4
 // CHECK-NEXT:    [[TMP0:%.*]] = load float, float* [[F_ADDR]], align 4
-// CHECK-NEXT:    [[TMP1:%.*]] = call i32 @llvm.s390.tdc.f32(float [[TMP0]], i64 15) [[ATTR2:#.*]]
+// CHECK-NEXT:    [[TMP1:%.*]] = call i32 @llvm.s390.tdc.f32(float [[TMP0]], i64 15) #[[ATTR2:[0-9]+]]
 // CHECK-NEXT:    ret i32 [[TMP1]]
 //
 int test_isnan_float(float f) {
   return __builtin_isnan(f);
 }
 
 // CHECK-LABEL: @test_isnan_double(
 // CHECK-NEXT:  entry:
 // CHECK-NEXT:    [[D_ADDR:%.*]] = alloca double, align 8
 // CHECK-NEXT:    store double [[D:%.*]], double* [[D_ADDR]], align 8
 // CHECK-NEXT:    [[TMP0:%.*]] = load double, double* [[D_ADDR]], align 8
-// CHECK-NEXT:    [[TMP1:%.*]] = call i32 @llvm.s390.tdc.f64(double [[TMP0]], i64 15) [[ATTR2]]
+// CHECK-NEXT:    [[TMP1:%.*]] = call i32 @llvm.s390.tdc.f64(double [[TMP0]], i64 15) #[[ATTR2]]
 // CHECK-NEXT:    ret i32 [[TMP1]]
 //
 int test_isnan_double(double d) {
   return __builtin_isnan(d);
 }
 
 // CHECK-LABEL: @test_isnan_long_double(
 // CHECK-NEXT:  entry:
 // CHECK-NEXT:    [[LD_ADDR:%.*]] = alloca fp128, align 8
 // CHECK-NEXT:    [[LD:%.*]] = load fp128, fp128* [[TMP0:%.*]], align 8
 // CHECK-NEXT:    store fp128 [[LD]], fp128* [[LD_ADDR]], align 8
 // CHECK-NEXT:    [[TMP1:%.*]] = load fp128, fp128* [[LD_ADDR]], align 8
-// CHECK-NEXT:    [[TMP2:%.*]] = call i32 @llvm.s390.tdc.f128(fp128 [[TMP1]], i64 15) [[ATTR2]]
+// CHECK-NEXT:    [[TMP2:%.*]] = call i32 @llvm.s390.tdc.f128(fp128 [[TMP1]], i64 15) #[[ATTR2]]
 // CHECK-NEXT:    ret i32 [[TMP2]]
 //
 int test_isnan_long_double(long double ld) {
   return __builtin_isnan(ld);
 }
 
+// CHECK-LABEL: @test_isinf_float(
+// CHECK-NEXT:  entry:
+// CHECK-NEXT:    [[F_ADDR:%.*]] = alloca float, align 4
+// CHECK-NEXT:    store float [[F:%.*]], float* [[F_ADDR]], align 4
+// CHECK-NEXT:    [[TMP0:%.*]] = load float, float* [[F_ADDR]], align 4
+// CHECK-NEXT:    [[TMP1:%.*]] = call i32 @llvm.s390.tdc.f32(float [[TMP0]], i64 48) #[[ATTR2]]
+// CHECK-NEXT:    ret i32 [[TMP1]]
+//
+int test_isinf_float(float f) {
+  return __builtin_isinf(f);
+}
+
+// CHECK-LABEL: @test_isinf_double(
+// CHECK-NEXT:  entry:
+// CHECK-NEXT:    [[D_ADDR:%.*]] = alloca double, align 8
+// CHECK-NEXT:    store double [[D:%.*]], double* [[D_ADDR]], align 8
+// CHECK-NEXT:    [[TMP0:%.*]] = load double, double* [[D_ADDR]], align 8
+// CHECK-NEXT:    [[TMP1:%.*]] = call i32 @llvm.s390.tdc.f64(double [[TMP0]], i64 48) #[[ATTR2]]
+// CHECK-NEXT:    ret i32 [[TMP1]]
+//
+int test_isinf_double(double d) {
+  return __builtin_isinf(d);
+}
+
+// CHECK-LABEL: @test_isinf_long_double(
+// CHECK-NEXT:  entry:
+// CHECK-NEXT:    [[LD_ADDR:%.*]] = alloca fp128, align 8
+// CHECK-NEXT:    [[LD:%.*]] = load fp128, fp128* [[TMP0:%.*]], align 8
+// CHECK-NEXT:    store fp128 [[LD]], fp128* [[LD_ADDR]], align 8
+// CHECK-NEXT:    [[TMP1:%.*]] = load fp128, fp128* [[LD_ADDR]], align 8
+// CHECK-NEXT:    [[TMP2:%.*]] = call i32 @llvm.s390.tdc.f128(fp128 [[TMP1]], i64 48) #[[ATTR2]]
+// CHECK-NEXT:    ret i32 [[TMP2]]
+//
+int test_isinf_long_double(long double ld) {
+  return __builtin_isinf(ld);
+}
+
+// CHECK-LABEL: @test_isfinite_float(
+// CHECK-NEXT:  entry:
+// CHECK-NEXT:    [[F_ADDR:%.*]] = alloca float, align 4
+// CHECK-NEXT:    store float [[F:%.*]], float* [[F_ADDR]], align 4
+// CHECK-NEXT:    [[TMP0:%.*]] = load float, float* [[F_ADDR]], align 4
+// CHECK-NEXT:    [[TMP1:%.*]] = call i32 @llvm.s390.tdc.f32(float [[TMP0]], i64 4032) #[[ATTR2]]
+// CHECK-NEXT:    ret i32 [[TMP1]]
+//
+int test_isfinite_float(float f) {
+  return __builtin_isfinite(f);
+}
+
+// CHECK-LABEL: @test_isfinite_double(
+// CHECK-NEXT:  entry:
+// CHECK-NEXT:    [[D_ADDR:%.*]] = alloca double, align 8
+// CHECK-NEXT:    store double [[D:%.*]], double* [[D_ADDR]], align 8
+// CHECK-NEXT:    [[TMP0:%.*]] = load double, double* [[D_ADDR]], align 8
+// CHECK-NEXT:    [[TMP1:%.*]] = call i32 @llvm.s390.tdc.f64(double [[TMP0]], i64 4032) #[[ATTR2]]
+// CHECK-NEXT:    ret i32 [[TMP1]]
+//
+int test_isfinite_double(double d) {
+  return __builtin_isfinite(d);
+}
+
+// CHECK-LABEL: @test_isfinite_long_double(
+// CHECK-NEXT:  entry:
+// CHECK-NEXT:    [[LD_ADDR:%.*]] = alloca fp128, align 8
+// CHECK-NEXT:    [[LD:%.*]] = load fp128, fp128* [[TMP0:%.*]], align 8
+// CHECK-NEXT:    store fp128 [[LD]], fp128* [[LD_ADDR]], align 8
+// CHECK-NEXT:    [[TMP1:%.*]] = load fp128, fp128* [[LD_ADDR]], align 8
+// CHECK-NEXT:    [[TMP2:%.*]] = call i32 @llvm.s390.tdc.f128(fp128 [[TMP1]], i64 4032) #[[ATTR2]]
+// CHECK-NEXT:    ret i32 [[TMP2]]
+//
+int test_isfinite_long_double(long double ld) {
+  return __builtin_isfinite(ld);
+}
+