[WebAssembly] Refactor WebAssemblyLowerEmscriptenException pass for setjmp/longjmp

This patch changes the code structure of
WebAssemblyLowerEmscriptenException pass to support both exception
handling and setjmp/longjmp. It also changes the name of the pass and
the source file.

1. Change the file/pass name to WebAssemblyLowerEmscriptenExceptions ->
WebAssemblyLowerEmscriptenEHSjLj to make it clear that it supports both
EH and SjLj
2. List function / global variable names at the top so they
can be changed easily
3. Some cosmetic changes

Patch by Heejin Ahn

Differential Revision: https://reviews.llvm.org/D23588

llvm-svn: 279075

1 files changed, 11 insertions, 4 deletions

diff --git a/llvm/lib/Target/WebAssembly/WebAssemblyTargetMachine.cpp b/llvm/lib/Target/WebAssembly/WebAssemblyTargetMachine.cpp
index e442cb1cded..1d21f2b33fd 100644
--- a/llvm/lib/Target/WebAssembly/WebAssemblyTargetMachine.cpp
+++ b/llvm/lib/Target/WebAssembly/WebAssemblyTargetMachine.cpp
@@ -30,18 +30,24 @@ using namespace llvm;
 #define DEBUG_TYPE "wasm"
 
 // Emscripten's asm.js-style exception handling
-static cl::opt<bool> EnableEmExceptionHandling(
+static cl::opt<bool> EnableEmException(
     "enable-emscripten-cxx-exceptions",
     cl::desc("WebAssembly Emscripten-style exception handling"),
     cl::init(false));
 
+// Emscripten's asm.js-style setjmp/longjmp handling
+static cl::opt<bool> EnableEmSjLj(
+    "enable-emscripten-sjlj",
+    cl::desc("WebAssembly Emscripten-style setjmp/longjmp handling"),
+    cl::init(false));
+
 extern "C" void LLVMInitializeWebAssemblyTarget() {
   // Register the target.
   RegisterTargetMachine<WebAssemblyTargetMachine> X(TheWebAssemblyTarget32);
   RegisterTargetMachine<WebAssemblyTargetMachine> Y(TheWebAssemblyTarget64);
 
   // Register exception handling pass to opt
-  initializeWebAssemblyLowerEmscriptenExceptionsPass(
+  initializeWebAssemblyLowerEmscriptenEHSjLjPass(
       *PassRegistry::getPassRegistry());
 }
 
@@ -160,8 +166,9 @@ void WebAssemblyPassConfig::addIRPasses() {
     addPass(createWebAssemblyOptimizeReturned());
 
   // Handle exceptions.
-  if (EnableEmExceptionHandling)
-    addPass(createWebAssemblyLowerEmscriptenExceptions());
+  if (EnableEmException || EnableEmSjLj)
+    addPass(createWebAssemblyLowerEmscriptenEHSjLj(EnableEmException,
+                                                   EnableEmSjLj));
 
   TargetPassConfig::addIRPasses();
 }