Add support for the unwind instruction
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@8408 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/CBackend/CBackend.cpp b/lib/Target/CBackend/CBackend.cpp
index 721ead0..073ce19 100644
--- a/lib/Target/CBackend/CBackend.cpp
+++ b/lib/Target/CBackend/CBackend.cpp
@@ -117,6 +117,7 @@
void visitBranchInst(BranchInst &I);
void visitSwitchInst(SwitchInst &I);
void visitInvokeInst(InvokeInst &I);
+ void visitUnwindInst(UnwindInst &I);
void visitPHINode(PHINode &I);
void visitBinaryOperator(Instruction &I);
@@ -980,6 +981,19 @@
}
+void CWriter::visitUnwindInst(UnwindInst &I) {
+ // The unwind instructions causes a control flow transfer out of the current
+ // function, unwinding the stack until a caller who used the invoke
+ // instruction is found. In this context, we code generated the invoke
+ // instruction to add an entry to the top of the jmpbuf_list. Thus, here we
+ // just have to longjmp to the specified handler.
+ Out << " if (__llvm_jmpbuf_list == 0) { /* llvm.unwind */\n"
+ << " printf(\"throw found with no handler!\\n\"); abort();\n"
+ << " }\n"
+ << " longjmp(__llvm_jmpbuf_list->buf, 1);\n";
+ emittedInvoke = true;
+}
+
static bool isGotoCodeNeccessary(BasicBlock *From, BasicBlock *To) {
// If PHI nodes need copies, we need the copy code...
if (isa<PHINode>(To->front()) ||