[PATCH] D72841: Add support for pragma float_control, to control precision and exception behavior at the source level

[Changpeng Fang via Phabricator via cfe-commits]

cfang added a comment.

-ffast-math flag got lost in the Builder after this change.

FMF.isFast() is true before  updateFastMathFlags(FMF, FPFeatures), but turns false after. 
It seems the Builder.FMF has been correctly set before, but I am not clear what FPFeatures should be at this point:

+static void setBuilderFlagsFromFPFeatures(CGBuilderTy &Builder,
+                                          CodeGenFunction &CGF,
+                                          FPOptions FPFeatures) {
+  auto NewRoundingBehavior = FPFeatures.getRoundingMode();
+  Builder.setDefaultConstrainedRounding(NewRoundingBehavior);
+  auto NewExceptionBehavior =
+      ToConstrainedExceptMD(FPFeatures.getExceptionMode());
+  Builder.setDefaultConstrainedExcept(NewExceptionBehavior);
+  auto FMF = Builder.getFastMathFlags();
+  updateFastMathFlags(FMF, FPFeatures);
+  Builder.setFastMathFlags(FMF);
+  assert((CGF.CurFuncDecl == nullptr || Builder.getIsFPConstrained() ||
+          isa<CXXConstructorDecl>(CGF.CurFuncDecl) ||
+          isa<CXXDestructorDecl>(CGF.CurFuncDecl) ||
+          (NewExceptionBehavior == llvm::fp::ebIgnore &&
+           NewRoundingBehavior == llvm::RoundingMode::NearestTiesToEven)) &&
+         "FPConstrained should be enabled on entire function");
+}


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D72841/new/

https://reviews.llvm.org/D72841