From af33b7b4a775073585f2037bf4cb56f1cd87d13c Mon Sep 17 00:00:00 2001
From: Bill Wendling <isanbard@gmail.com>
Date: Wed, 4 Aug 2010 23:36:02 +0000
Subject: [PATCH] The lower invoke pass needs to have unreachable code
 elimination run after it because it could create such things. This fixes a
 MingW buildbot test failure.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@110279 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/CodeGen/LLVMTargetMachine.cpp         |  6 ++--
 test/CodeGen/X86/2010-08-04-MingWCrash.ll | 39 +++++++++++++++++++++++
 2 files changed, 43 insertions(+), 2 deletions(-)
 create mode 100644 test/CodeGen/X86/2010-08-04-MingWCrash.ll

diff --git a/lib/CodeGen/LLVMTargetMachine.cpp b/lib/CodeGen/LLVMTargetMachine.cpp
index 807ceefd137..9d8258f1916 100644
--- a/lib/CodeGen/LLVMTargetMachine.cpp
+++ b/lib/CodeGen/LLVMTargetMachine.cpp
@@ -288,13 +288,15 @@ bool LLVMTargetMachine::addCommonCodeGenPasses(PassManagerBase &PM,
     // pad is shared by multiple invokes and is also a target of a normal
     // edge from elsewhere.
     PM.add(createSjLjEHPass(getTargetLowering()));
-    PM.add(createDwarfEHPass(this, OptLevel==CodeGenOpt::None));
-    break;
+    // FALLTHROUGH
   case ExceptionHandling::Dwarf:
     PM.add(createDwarfEHPass(this, OptLevel==CodeGenOpt::None));
     break;
   case ExceptionHandling::None:
     PM.add(createLowerInvokePass(getTargetLowering()));
+
+    // The lower invoke pass may create unreachable code. Remove it.
+    PM.add(createUnreachableBlockEliminationPass());
     break;
   }
 
diff --git a/test/CodeGen/X86/2010-08-04-MingWCrash.ll b/test/CodeGen/X86/2010-08-04-MingWCrash.ll
new file mode 100644
index 00000000000..98a0887c0e6
--- /dev/null
+++ b/test/CodeGen/X86/2010-08-04-MingWCrash.ll
@@ -0,0 +1,39 @@
+; RUN: llc < %s -mtriple=i386-pc-mingw32
+
+define void @func() nounwind {
+invoke.cont:
+  %call = tail call i8* @malloc()
+  %a = invoke i32 @bar()
+          to label %bb1 unwind label %lpad
+
+bb1:
+  ret void
+
+lpad:
+  %exn = tail call i8* @llvm.eh.exception() nounwind
+  %eh.selector = tail call i32 (i8*, i8*, ...)* @llvm.eh.selector(i8* %exn, i8* bitcast (i32 (...)* @__gxx_personality_v0 to i8*), i32 1, i8* null) nounwind
+  %ehspec.fails = icmp slt i32 %eh.selector, 0
+  br i1 %ehspec.fails, label %ehspec.unexpected, label %cleanup
+
+cleanup:
+  tail call void @_Unwind_Resume_or_Rethrow(i8* %exn) noreturn nounwind
+  unreachable
+
+ehspec.unexpected:
+  tail call void @__cxa_call_unexpected(i8* %exn) noreturn nounwind
+  unreachable
+}
+
+declare noalias i8* @malloc()
+
+declare i8* @llvm.eh.exception() nounwind readonly
+
+declare i32 @__gxx_personality_v0(...)
+
+declare i32 @llvm.eh.selector(i8*, i8*, ...) nounwind
+
+declare void @_Unwind_Resume_or_Rethrow(i8*)
+
+declare void @__cxa_call_unexpected(i8*)
+
+declare i32 @bar()