From: Heejin Ahn <aheejin@gmail.com>
Date: Tue, 17 Apr 2018 21:19:21 +0000 (+0000)
Subject: [WebAssembly] Add an assertion for an invalid CFG
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=2b8158f441da74d8432c7629b005a7107a44186b;p=platform%2Fupstream%2Fllvm.git

[WebAssembly] Add an assertion for an invalid CFG

Summary:
It was not easy to provide a test case for D45648 (rL330079) because the bug
didn't manifest itself in the set of currently valid IRs. Added an assertion to
check this faster, thanks to @dblaikie's suggestion.

Reviewers: dblaikie

Subscribers: jfb, dschuff, sbc100, jgravelle-google, llvm-commits, dblaikie

Differential Revision: https://reviews.llvm.org/D45711

llvm-svn: 330217
---

diff --git a/llvm/lib/Target/WebAssembly/WebAssemblyCFGStackify.cpp b/llvm/lib/Target/WebAssembly/WebAssemblyCFGStackify.cpp
index 12664e6..9e0a945 100644
--- a/llvm/lib/Target/WebAssembly/WebAssemblyCFGStackify.cpp
+++ b/llvm/lib/Target/WebAssembly/WebAssemblyCFGStackify.cpp
@@ -145,6 +145,9 @@ static void PlaceBlockMarker(
            std::prev(InsertPos)->getOpcode() != WebAssembly::END_LOOP)
       --InsertPos;
   }
+  // The header block in which a 'block' mark will be inserted should have a
+  // terminator because it is branching to a non-layout successor.
+  assert(InsertPos != Header->end());
 
   // Add the BLOCK.
   MachineInstr *Begin =