[WebAssembly] Move CFG-changing passes before RegStackify
Summary:
FixIrreducibleControlFlow and LateEHPrepare both possibly modify CFG and
create new registers. There seems to be no reason these passes go after
register-related optimization passes (PrepareForLiveIntervals,
OptimizeLiveIntervals, StoreResults, RegStackify, and RegColoring), and
this also possibly create new optimization opportunities. I think we
should put all current and future optimization passes before RegStackify
(and related passes) unless there's a reason not to.
Reviewers: kripken
Subscribers: dschuff, sbc100, sunfish, jgravelle-google, llvm-commits
Differential Revision: https://reviews.llvm.org/D56356
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@350596 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/WebAssembly/WebAssemblyTargetMachine.cpp b/lib/Target/WebAssembly/WebAssemblyTargetMachine.cpp
index a6fb782..05bd5926 100644
--- a/lib/Target/WebAssembly/WebAssemblyTargetMachine.cpp
+++ b/lib/Target/WebAssembly/WebAssemblyTargetMachine.cpp
@@ -298,6 +298,12 @@
// order of the arguments.
addPass(createWebAssemblyCallIndirectFixup());
+ // Eliminate multiple-entry loops.
+ addPass(createWebAssemblyFixIrreducibleControlFlow());
+
+ // Do various transformations for exception handling.
+ addPass(createWebAssemblyLateEHPrepare());
+
if (getOptLevel() != CodeGenOpt::None) {
// LiveIntervals isn't commonly run this late. Re-establish preconditions.
addPass(createWebAssemblyPrepareForLiveIntervals());
@@ -320,17 +326,9 @@
addPass(createWebAssemblyRegColoring());
}
- // Eliminate multiple-entry loops. Do this before inserting explicit get_local
- // and set_local operators because we create a new variable that we want
- // converted into a local.
- addPass(createWebAssemblyFixIrreducibleControlFlow());
-
// Insert explicit get_local and set_local operators.
addPass(createWebAssemblyExplicitLocals());
- // Do various transformations for exception handling
- addPass(createWebAssemblyLateEHPrepare());
-
// Sort the blocks of the CFG into topological order, a prerequisite for
// BLOCK and LOOP markers.
addPass(createWebAssemblyCFGSort());
