Make clang to mark static stack allocations with lifetime markers to enable a more aggressive stack coloring.
Patch by John McCall with help by Shuxin Yang.
rdar://13115369
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@177819 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/CGStmt.cpp b/lib/CodeGen/CGStmt.cpp
index 9e7ddfb..06f7460 100644
--- a/lib/CodeGen/CGStmt.cpp
+++ b/lib/CodeGen/CGStmt.cpp
@@ -319,6 +319,12 @@
}
void CodeGenFunction::EmitLabel(const LabelDecl *D) {
+ // Add this label to the current lexical scope if we're within any
+ // normal cleanups. Jumps "in" to this label --- when permitted by
+ // the language --- may need to be routed around such cleanups.
+ if (EHStack.hasNormalCleanups() && CurLexicalScope)
+ CurLexicalScope->addLabel(D);
+
JumpDest &Dest = LabelMap[D];
// If we didn't need a forward reference to this label, just go
@@ -330,16 +336,36 @@
// it from the branch-fixups list.
} else {
assert(!Dest.getScopeDepth().isValid() && "already emitted label!");
- Dest = JumpDest(Dest.getBlock(),
- EHStack.stable_begin(),
- Dest.getDestIndex());
-
+ Dest.setScopeDepth(EHStack.stable_begin());
ResolveBranchFixups(Dest.getBlock());
}
EmitBlock(Dest.getBlock());
}
+/// Change the cleanup scope of the labels in this lexical scope to
+/// match the scope of the enclosing context.
+void CodeGenFunction::LexicalScope::rescopeLabels() {
+ assert(!Labels.empty());
+ EHScopeStack::stable_iterator innermostScope
+ = CGF.EHStack.getInnermostNormalCleanup();
+
+ // Change the scope depth of all the labels.
+ for (SmallVectorImpl<const LabelDecl*>::const_iterator
+ i = Labels.begin(), e = Labels.end(); i != e; ++i) {
+ assert(CGF.LabelMap.count(*i));
+ JumpDest &dest = CGF.LabelMap.find(*i)->second;
+ assert(dest.getScopeDepth().isValid());
+ assert(innermostScope.encloses(dest.getScopeDepth()));
+ dest.setScopeDepth(innermostScope);
+ }
+
+ // Reparent the labels if the new scope also has cleanups.
+ if (innermostScope != EHScopeStack::stable_end() && ParentScope) {
+ ParentScope->Labels.append(Labels.begin(), Labels.end());
+ }
+}
+
void CodeGenFunction::EmitLabelStmt(const LabelStmt &S) {
EmitLabel(S.getDecl());