Implement support for -fwrapv, rdar://7221421
As part of this, pull together trapv handling into the same enum.
This also add support for NSW multiplies.
This also makes PCH disagreement on overflow behavior silent, since it
really doesn't matter except for warnings and codegen (no macros get
defined etc).
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@106956 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Frontend/CompilerInvocation.cpp b/lib/Frontend/CompilerInvocation.cpp
index e7a75a6..76770ae 100644
--- a/lib/Frontend/CompilerInvocation.cpp
+++ b/lib/Frontend/CompilerInvocation.cpp
@@ -549,8 +549,11 @@
Res.push_back("-femit-all-decls");
if (Opts.MathErrno)
Res.push_back("-fmath-errno");
- if (Opts.OverflowChecking)
- Res.push_back("-ftrapv");
+ switch (Opts.getSignedOverflowBehavior()) {
+ case LangOptions::SOB_Undefined: break;
+ case LangOptions::SOB_Defined: Res.push_back("-fwrapv"); break;
+ case LangOptions::SOB_Trapping: Res.push_back("-ftrapv"); break;
+ }
if (Opts.HeinousExtensions)
Res.push_back("-fheinous-gnu-extensions");
// Optimize is implicit.
@@ -1257,8 +1260,11 @@
if (Args.hasArg(OPT_fvisibility_inlines_hidden))
Opts.InlineVisibilityHidden = 1;
-
- Opts.OverflowChecking = Args.hasArg(OPT_ftrapv);
+
+ if (Args.hasArg(OPT_ftrapv))
+ Opts.setSignedOverflowBehavior(LangOptions::SOB_Trapping);
+ else if (Args.hasArg(OPT_fwrapv))
+ Opts.setSignedOverflowBehavior(LangOptions::SOB_Defined);
// Mimicing gcc's behavior, trigraphs are only enabled if -trigraphs
// is specified, or -std is set to a conforming mode.