Introduce cleanup scopes for "if" statements in two places:
- Outside the "if", to ensure that we destroy the condition variable
at the end of the "if" statement rather than at the end of the
block containing the "if" statement.
- Inside the "then" and "else" branches, so that we emit then- or
else-local cleanups at the end of the corresponding block when the
block is not a compound statement.
To make adding these new cleanup scopes easier (and since
switch/do/while will all need the same treatment), added the
CleanupScope RAII object to introduce a new cleanup scope and make
sure it gets cleaned up.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@89773 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/CGStmt.cpp b/lib/CodeGen/CGStmt.cpp
index 1c3f357..51b7cf8 100644
--- a/lib/CodeGen/CGStmt.cpp
+++ b/lib/CodeGen/CGStmt.cpp
@@ -153,9 +153,7 @@
}
// Keep track of the current cleanup stack depth.
- size_t CleanupStackDepth = CleanupEntries.size();
- bool OldDidCallStackSave = DidCallStackSave;
- DidCallStackSave = false;
+ CleanupScope Scope(*this);
for (CompoundStmt::const_body_iterator I = S.body_begin(),
E = S.body_end()-GetLast; I != E; ++I)
@@ -185,10 +183,6 @@
RV = EmitAnyExpr(cast<Expr>(LastStmt), AggLoc);
}
- DidCallStackSave = OldDidCallStackSave;
-
- EmitCleanupBlocks(CleanupStackDepth);
-
return RV;
}
@@ -294,8 +288,10 @@
void CodeGenFunction::EmitIfStmt(const IfStmt &S) {
// C99 6.8.4.1: The first substatement is executed if the expression compares
// unequal to 0. The condition must be a scalar type.
+ CleanupScope ConditionScope(*this);
+
if (S.getConditionVariable())
- EmitDecl(*S.getConditionVariable());
+ EmitLocalBlockVarDecl(*S.getConditionVariable());
// If the condition constant folds and can be elided, try to avoid emitting
// the condition and the dead arm of the if/else.
@@ -308,8 +304,10 @@
// If the skipped block has no labels in it, just emit the executed block.
// This avoids emitting dead code and simplifies the CFG substantially.
if (!ContainsLabel(Skipped)) {
- if (Executed)
+ if (Executed) {
+ CleanupScope ExecutedScope(*this);
EmitStmt(Executed);
+ }
return;
}
}
@@ -324,14 +322,20 @@
EmitBranchOnBoolExpr(S.getCond(), ThenBlock, ElseBlock);
// Emit the 'then' code.
- EmitBlock(ThenBlock);
- EmitStmt(S.getThen());
+ EmitBlock(ThenBlock);
+ {
+ CleanupScope ThenScope(*this);
+ EmitStmt(S.getThen());
+ }
EmitBranch(ContBlock);
// Emit the 'else' code if present.
if (const Stmt *Else = S.getElse()) {
EmitBlock(ElseBlock);
- EmitStmt(Else);
+ {
+ CleanupScope ElseScope(*this);
+ EmitStmt(Else);
+ }
EmitBranch(ContBlock);
}