Move VLA processing logic from LiveVariables to CFG construction. This way all dataflow analyses "see" the VLA size expressions.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@56655 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/AST/CFG.cpp b/lib/AST/CFG.cpp
index b18f904..c0b1b96 100644
--- a/lib/AST/CFG.cpp
+++ b/lib/AST/CFG.cpp
@@ -467,6 +467,18 @@
return WalkAST_VisitChildren(Terminator);
}
+static VariableArrayType* FindVA(Type* t) {
+ while (ArrayType* vt = dyn_cast<ArrayType>(t)) {
+ if (VariableArrayType* vat = dyn_cast<VariableArrayType>(vt))
+ if (vat->getSizeExpr())
+ return vat;
+
+ t = vt->getElementType().getTypePtr();
+ }
+
+ return 0;
+}
+
/// WalkAST_VisitDeclSubExpr - Utility method to add block-level expressions
/// for initializers in Decls.
CFGBlock* CFGBuilder::WalkAST_VisitDeclSubExpr(ScopedDecl* D) {
@@ -477,18 +489,22 @@
Expr* Init = VD->getInit();
- if (!Init)
- return Block;
-
- // Optimization: Don't create separate block-level statements for literals.
- switch (Init->getStmtClass()) {
- case Stmt::IntegerLiteralClass:
- case Stmt::CharacterLiteralClass:
- case Stmt::StringLiteralClass:
- break;
- default:
- Block = addStmt(Init);
+ if (Init) {
+ // Optimization: Don't create separate block-level statements for literals.
+ switch (Init->getStmtClass()) {
+ case Stmt::IntegerLiteralClass:
+ case Stmt::CharacterLiteralClass:
+ case Stmt::StringLiteralClass:
+ break;
+ default:
+ Block = addStmt(Init);
+ }
}
+
+ // If the type of VD is a VLA, then we must process its size expressions.
+ for (VariableArrayType* VA = FindVA(VD->getType().getTypePtr()); VA != 0;
+ VA = FindVA(VA->getElementType().getTypePtr()))
+ Block = addStmt(VA->getSizeExpr());
return Block;
}
diff --git a/lib/Analysis/LiveVariables.cpp b/lib/Analysis/LiveVariables.cpp
index e82c1e0..58affbf 100644
--- a/lib/Analysis/LiveVariables.cpp
+++ b/lib/Analysis/LiveVariables.cpp
@@ -226,18 +226,6 @@
Visit(B->getRHS());
}
-static VariableArrayType* FindVA(Type* t) {
- while (ArrayType* vt = dyn_cast<ArrayType>(t)) {
- if (VariableArrayType* vat = dyn_cast<VariableArrayType>(vt))
- if (vat->getSizeExpr())
- return vat;
-
- t = vt->getElementType().getTypePtr();
- }
-
- return NULL;
-}
-
void TransferFuncs::VisitDeclStmt(DeclStmt* DS) {
// Declarations effectively "kill" a variable since they cannot
// possibly be live before they are declared.
@@ -253,14 +241,6 @@
// Update liveness information by killing the VarDecl.
unsigned bit = AD.getIdx(VD);
LiveState.getDeclBit(bit) = Dead | AD.AlwaysLive.getDeclBit(bit);
-
- // If the type of VD is a VLA, then we must process its size expressions.
- // These expressions are evaluated before the variable comes into scope,
- // so in a reverse dataflow analysis we evaluate them last.
- for (VariableArrayType* VA = FindVA(VD->getType().getTypePtr()); VA != 0;
- VA = FindVA(VA->getElementType().getTypePtr()))
- Visit(VA->getSizeExpr());
-
}
}