Add support for floating-point option `ffp-eval-method` and for

`pragma clang fp eval_method`.

Differential Revision: https://reviews.llvm.org/D109239

1 files changed, 21 insertions, 0 deletions

diff --git a/clang/lib/Sema/Sema.cpp b/clang/lib/Sema/Sema.cpp
index 7b57c8d..db3eda6 100644
--- a/clang/lib/Sema/Sema.cpp
+++ b/clang/lib/Sema/Sema.cpp
@@ -242,6 +242,15 @@ Sema::Sema(Preprocessor &pp, ASTContext &ctxt, ASTConsumer &consumer,
   SemaPPCallbackHandler = Callbacks.get();
   PP.addPPCallbacks(std::move(Callbacks));
   SemaPPCallbackHandler->set(*this);
+  if (getLangOpts().getFPEvalMethod() == LangOptions::FEM_UnsetOnCommandLine)
+    // Use setting from TargetInfo.
+    PP.setCurrentFPEvalMethod(SourceLocation(),
+                              ctxt.getTargetInfo().getFPEvalMethod());
+  else
+    // Set initial value of __FLT_EVAL_METHOD__ from the command line.
+    PP.setCurrentFPEvalMethod(SourceLocation(),
+                              getLangOpts().getFPEvalMethod());
+  CurFPFeatures.setFPEvalMethod(PP.getCurrentFPEvalMethod());
 }
 
 // Anchor Sema's type info to this TU.
@@ -2630,3 +2639,15 @@ const llvm::MapVector<FieldDecl *, Sema::DeleteLocs> &
 Sema::getMismatchingDeleteExpressions() const {
   return DeleteExprs;
 }
+
+Sema::FPFeaturesStateRAII::FPFeaturesStateRAII(Sema &S)
+    : S(S), OldFPFeaturesState(S.CurFPFeatures),
+      OldOverrides(S.FpPragmaStack.CurrentValue),
+      OldEvalMethod(S.PP.getCurrentFPEvalMethod()),
+      OldFPPragmaLocation(S.PP.getLastFPEvalPragmaLocation()) {}
+
+Sema::FPFeaturesStateRAII::~FPFeaturesStateRAII() {
+  S.CurFPFeatures = OldFPFeaturesState;
+  S.FpPragmaStack.CurrentValue = OldOverrides;
+  S.PP.setCurrentFPEvalMethod(OldFPPragmaLocation, OldEvalMethod);
+}