[WebAssembly] Use Windows EH instructions for Wasm EH
Summary:
Because wasm control flow needs to be structured, using WinEH
instructions to support wasm EH brings several benefits. This patch
makes wasm EH uses Windows EH instructions, with some changes:
1. Because wasm uses a single catch block to catch all C++ exceptions,
this merges all catch clauses into a single catchpad, within which we
test the EH selector as in Itanium EH.
2. Generates a call to `__clang_call_terminate` in case a cleanup
throws. Wasm does not have a runtime to handle this.
3. In case there is no catch-all clause, inserts a call to
`__cxa_rethrow` at the end of a catchpad in order to unwind to an
enclosing EH scope.
Reviewers: majnemer, dschuff
Subscribers: jfb, sbc100, jgravelle-google, sunfish, cfe-commits
Differential Revision: https://reviews.llvm.org/D44931
llvm-svn: 333703
diff --git a/clang/lib/CodeGen/CodeGenFunction.h b/clang/lib/CodeGen/CodeGenFunction.h
index 56b07e5..3ee66b0 100644
--- a/clang/lib/CodeGen/CodeGenFunction.h
+++ b/clang/lib/CodeGen/CodeGenFunction.h
@@ -877,7 +877,8 @@
llvm::BasicBlock *getEHResumeBlock(bool isCleanup);
llvm::BasicBlock *getEHDispatchBlock(EHScopeStack::stable_iterator scope);
- llvm::BasicBlock *getMSVCDispatchBlock(EHScopeStack::stable_iterator scope);
+ llvm::BasicBlock *
+ getFuncletEHDispatchBlock(EHScopeStack::stable_iterator scope);
/// An object to manage conditionally-evaluated expressions.
class ConditionalEvaluation {