Add support for C++0x's range-based for loops, as specified by the C++11 draft standard (N3291).
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@129541 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/CGStmt.cpp b/lib/CodeGen/CGStmt.cpp
index e72d5c7..7a1ce19 100644
--- a/lib/CodeGen/CGStmt.cpp
+++ b/lib/CodeGen/CGStmt.cpp
@@ -153,6 +153,9 @@
case Stmt::CXXTryStmtClass:
EmitCXXTryStmt(cast<CXXTryStmt>(*S));
break;
+ case Stmt::CXXForRangeStmtClass:
+ EmitCXXForRangeStmt(cast<CXXForRangeStmt>(*S));
+ break;
}
}
@@ -636,6 +639,80 @@
EmitBlock(LoopExit.getBlock(), true);
}
+void CodeGenFunction::EmitCXXForRangeStmt(const CXXForRangeStmt &S) {
+ JumpDest LoopExit = getJumpDestInCurrentScope("for.end");
+
+ RunCleanupsScope ForScope(*this);
+
+ CGDebugInfo *DI = getDebugInfo();
+ if (DI) {
+ DI->setLocation(S.getSourceRange().getBegin());
+ DI->EmitRegionStart(Builder);
+ }
+
+ // Evaluate the first pieces before the loop.
+ EmitStmt(S.getRangeStmt());
+ EmitStmt(S.getBeginEndStmt());
+
+ // Start the loop with a block that tests the condition.
+ // If there's an increment, the continue scope will be overwritten
+ // later.
+ llvm::BasicBlock *CondBlock = createBasicBlock("for.cond");
+ EmitBlock(CondBlock);
+
+ // If there are any cleanups between here and the loop-exit scope,
+ // create a block to stage a loop exit along.
+ llvm::BasicBlock *ExitBlock = LoopExit.getBlock();
+ if (ForScope.requiresCleanups())
+ ExitBlock = createBasicBlock("for.cond.cleanup");
+
+ // The loop body, consisting of the specified body and the loop variable.
+ llvm::BasicBlock *ForBody = createBasicBlock("for.body");
+
+ // The body is executed if the expression, contextually converted
+ // to bool, is true.
+ llvm::Value *BoolCondVal = EvaluateExprAsBool(S.getCond());
+ Builder.CreateCondBr(BoolCondVal, ForBody, ExitBlock);
+
+ if (ExitBlock != LoopExit.getBlock()) {
+ EmitBlock(ExitBlock);
+ EmitBranchThroughCleanup(LoopExit);
+ }
+
+ EmitBlock(ForBody);
+
+ // Create a block for the increment. In case of a 'continue', we jump there.
+ JumpDest Continue = getJumpDestInCurrentScope("for.inc");
+
+ // Store the blocks to use for break and continue.
+ BreakContinueStack.push_back(BreakContinue(LoopExit, Continue));
+
+ {
+ // Create a separate cleanup scope for the loop variable and body.
+ RunCleanupsScope BodyScope(*this);
+ EmitStmt(S.getLoopVarStmt());
+ EmitStmt(S.getBody());
+ }
+
+ // If there is an increment, emit it next.
+ EmitBlock(Continue.getBlock());
+ EmitStmt(S.getInc());
+
+ BreakContinueStack.pop_back();
+
+ EmitBranch(CondBlock);
+
+ ForScope.ForceCleanup();
+
+ if (DI) {
+ DI->setLocation(S.getSourceRange().getEnd());
+ DI->EmitRegionEnd(Builder);
+ }
+
+ // Emit the fall-through block.
+ EmitBlock(LoopExit.getBlock(), true);
+}
+
void CodeGenFunction::EmitReturnOfRValue(RValue RV, QualType Ty) {
if (RV.isScalar()) {
Builder.CreateStore(RV.getScalarVal(), ReturnValue);