Fix bug with -ffp-contract=fast-honor-pragmas

clang/docs/ReleaseNotes.rst

@@ -310,6 +310,9 @@ Miscellaneous Clang Crashes Fixed
 - Fixed a crash caused by long chains of ``sizeof`` and other similar operators
   that can be followed by a non-parenthesized expression. (#GH45061)
 
+- Fixed an crash when compiling ``#pragma STDC FP_CONTRACT DEFAULT`` with
+  ``-ffp-contract=fast-honor-pragmas``. (#GH104830)
+
 - Fixed a crash when function has more than 65536 parameters.
   Now a diagnostic is emitted. (#GH35741)
 

clang/lib/Sema/SemaAttr.cpp

@@ -1269,13 +1269,12 @@ void Sema::ActOnPragmaFPContract(SourceLocation Loc,
     NewFPFeatures.setAllowFPContractWithinStatement();
     break;
   case LangOptions::FPM_Fast:
+  case LangOptions::FPM_FastHonorPragmas:
     NewFPFeatures.setAllowFPContractAcrossStatement();
     break;
   case LangOptions::FPM_Off:
     NewFPFeatures.setDisallowFPContract();
     break;
-  case LangOptions::FPM_FastHonorPragmas:
-    llvm_unreachable("Should not happen");
   }
   FpPragmaStack.Act(Loc, Sema::PSK_Set, StringRef(), NewFPFeatures);
   CurFPFeatures = NewFPFeatures.applyOverrides(getLangOpts());

clang/test/CodeGen/ffp-contract-fast-honor-pramga-option.cpp

@@ -0,0 +1,37 @@
+// RUN: %clang_cc1 -O3 -ffp-contract=fast-honor-pragmas -triple %itanium_abi_triple -emit-llvm -o - %s | FileCheck %s
+
+float fp_contract_1(float a, float b, float c) {
+  // CHECK-LABEL: fp_contract_1fff(
+  // CHECK: fmul contract float
+  // CHECK: fadd contract float
+  return a * b + c;
+}
+
+float fp_contract_2(float a, float b, float c) {
+  // CHECK-LABEL: fp_contract_2fff(
+  // CHECK: fmul contract float
+  // CHECK: fsub contract float
+  return a * b - c;
+}
+
+void fp_contract_3(float *a, float b, float c) {
+  // CHECK-LABEL: fp_contract_3Pfff(
+  // CHECK: fmul contract float
+  // CHECK: fadd contract float
+  a[0] += b * c;
+}
+
+void fp_contract_4(float *a, float b, float c) {
+  // CHECK-LABEL: fp_contract_4Pfff(
+  // CHECK: fmul contract float
+  // CHECK: fsub contract float
+  a[0] -= b * c;
+}
+
+float fp_contract_5(float a, float b, float c) {
+  // CHECK-LABEL: fp_contract_5fff(
+  // CHECK: fmul contract float
+  // CHECK: fadd contract float
+  float t = a * b;
+  return t + c;
+}

clang/test/CodeGen/ffp-contract-fhp-pragma-override.cpp

@@ -0,0 +1,151 @@
+// RUN: %clang_cc1 -O3 -ffp-contract=fast-honor-pragmas -triple %itanium_abi_triple -emit-llvm -o - %s | FileCheck %s
+
+float fp_contract_on_1(float a, float b, float c) {
+  // CHECK-LABEL: fp_contract_on_1fff(
+  // CHECK: call float @llvm.fmuladd.f32(float {{.*}}, float {{.*}}, float {{.*}})
+  #pragma STDC FP_CONTRACT ON
+  return a * b + c;
+}
+
+float fp_contract_on_2(float a, float b, float c) {
+  // CHECK-LABEL: fp_contract_on_2fff(
+  // CHECK: fmul float
+  // CHECK: fadd float
+  #pragma STDC FP_CONTRACT ON
+  float t = a * b;
+  return t + c;
+}
+
+float fp_contract_off_1(float a, float b, float c) {
+  // CHECK-LABEL: fp_contract_off_1fff(
+  // CHECK: fmul float
+  // CHECK: fadd float
+  #pragma STDC FP_CONTRACT OFF
+  return a * b + c;
+}
+
+float fp_contract_off_2(float a, float b, float c) {
+  // CHECK-LABEL: fp_contract_off_2fff(
+  // CHECK: fmul float
+  // CHECK: fadd float
+  #pragma STDC FP_CONTRACT OFF
+  float t = a * b;
+  return t + c;
+}
+
+float fp_contract_default_1(float a, float b, float c) {
+  // CHECK-LABEL: fp_contract_default_1fff(
+  // CHECK: fmul contract float
+  // CHECK: fadd contract float
+  #pragma STDC FP_CONTRACT DEFAULT
+  return a * b + c;
+}
+
+float fp_contract_default_2(float a, float b, float c) {
+  // CHECK-LABEL: fp_contract_default_2fff(
+  // CHECK: fmul contract float
+  // CHECK: fadd contract float
+  #pragma STDC FP_CONTRACT DEFAULT
+  float t = a * b;
+  return t + c;
+}
+
+float fp_contract_clang_on_1(float a, float b, float c) {
+  // CHECK-LABEL: fp_contract_clang_on_1fff(
+  // CHECK: call float @llvm.fmuladd.f32(float {{.*}}, float {{.*}}, float {{.*}})
+  #pragma clang fp contract(on)
+  return a * b + c;
+}
+
+float fp_contract_clang_on_2(float a, float b, float c) {
+  // CHECK-LABEL: fp_contract_clang_on_2fff(
+  // CHECK: fmul float
+  // CHECK: fadd float
+  #pragma clang fp contract(on)
+  float t = a * b;
+  return t + c;
+}
+
+float fp_contract_clang_off_1(float a, float b, float c) {
+  // CHECK-LABEL: fp_contract_clang_off_1fff(
+  // CHECK: fmul float
+  // CHECK: fadd float
+  #pragma clang fp contract(off)
+  return a * b + c;
+}
+
+float fp_contract_clang_off_2(float a, float b, float c) {
+  // CHECK-LABEL: fp_contract_clang_off_2fff(
+  // CHECK: fmul float
+  // CHECK: fadd float
+  #pragma clang fp contract(off)
+  float t = a * b;
+  return t + c;
+}
+
+float fp_contract_clang_fast_1(float a, float b, float c) {
+  // CHECK-LABEL: fp_contract_clang_fast_1fff(
+  // CHECK: fmul contract float
+  // CHECK: fadd contract float
+  #pragma clang fp contract(fast)
+  return a * b + c;
+}
+
+float fp_contract_clang_fast_2(float a, float b, float c) {
+  // CHECK-LABEL: fp_contract_clang_fast_2fff(
+  // CHECK: fmul contract float
+  // CHECK: fadd contract float
+  #pragma clang fp contract(fast)
+  float t = a * b;
+  return t + c;
+}
+
+#pragma STDC FP_CONTRACT ON
+
+float fp_contract_global_on_1(float a, float b, float c) {
+  // CHECK-LABEL: fp_contract_global_on_1fff(
+  // CHECK: call float @llvm.fmuladd.f32(float {{.*}}, float {{.*}}, float {{.*}})
+  return a * b + c;
+}
+
+float fp_contract_global_on_2(float a, float b, float c) {
+  // CHECK-LABEL: fp_contract_global_on_2fff(
+  // CHECK: fmul float
+  // CHECK: fadd float
+  float t = a * b;
+  return t + c;
+}
+
+#pragma STDC FP_CONTRACT OFF
+
+float fp_contract_global_off_1(float a, float b, float c) {
+  // CHECK-LABEL: fp_contract_global_off_1fff(
+  // CHECK: fmul float
+  // CHECK: fadd float
+  return a * b + c;
+}
+
+float fp_contract_global_off_2(float a, float b, float c) {
+  // CHECK-LABEL: fp_contract_global_off_2fff(
+  // CHECK: fmul float
+  // CHECK: fadd float
+  float t = a * b;
+  return t + c;
+}
+
+#pragma STDC FP_CONTRACT DEFAULT
+
+float fp_contract_global_default_1(float a, float b, float c) {
+  // CHECK-LABEL: fp_contract_global_default_1fff(
+  // CHECK: fmul contract float
+  // CHECK: fadd contract float
+  return a * b + c;
+}
+
+float fp_contract_global_default_2(float a, float b, float c) {
+  // CHECK-LABEL: fp_contract_global_default_2fff(
+  // CHECK: fmul contract float
+  // CHECK: fadd contract float
+  float t = a * b;
+  return t + c;
+}