Implement support for the unwind intrinsic in the CBE

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@8116 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 13 insertions, 0 deletions

diff --git a/lib/Target/CBackend/Writer.cpp b/lib/Target/CBackend/Writer.cpp
index 4bc354bdee..7f2b14d327 100644
--- a/lib/Target/CBackend/Writer.cpp
+++ b/lib/Target/CBackend/Writer.cpp
@@ -1137,6 +1137,19 @@ void CWriter::visitCallInst(CallInst &I) {
         writeOperand(I.getOperand(2));
         Out << ")";
         return;
+
+      case LLVMIntrinsic::unwind:
+        // The unwind intrinsic calls 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)";
+        return;
+
         
       case LLVMIntrinsic::setjmp:
       case LLVMIntrinsic::sigsetjmp: