From: Geoff Berry <gberry@codeaurora.org>
Date: Mon, 12 Dec 2016 19:12:41 +0000 (+0000)
Subject: [LiveRangeEdit] Add assert string and descriptive comment.
X-Git-Tag: llvmorg-4.0.0-rc1~2319
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=d73420d591380d25c34dbc9a1a35c2751ad33b71;p=platform%2Fupstream%2Fllvm.git

[LiveRangeEdit] Add assert string and descriptive comment.

llvm-svn: 289456
---

diff --git a/llvm/lib/CodeGen/LiveRangeEdit.cpp b/llvm/lib/CodeGen/LiveRangeEdit.cpp
index 88fed62..918be47 100644
--- a/llvm/lib/CodeGen/LiveRangeEdit.cpp
+++ b/llvm/lib/CodeGen/LiveRangeEdit.cpp
@@ -273,7 +273,9 @@ void LiveRangeEdit::eliminateDeadDef(MachineInstr *MI, ToShrinkSet &ToShrink,
   bool isOrigDef = false;
   unsigned Dest;
   if (VRM && MI->getOperand(0).isReg() && MI->getOperand(0).isDef()) {
-    assert(MI->getDesc().getNumDefs() == 1);
+    // It is assumed that callers of eliminateDeadDefs() will never pass in dead
+    // instructions with multiple virtual register defs.
+    assert(MI->getDesc().getNumDefs() == 1 && "Unexpected instruction with multiple defs.");
     Dest = MI->getOperand(0).getReg();
     unsigned Original = VRM->getOriginal(Dest);
     LiveInterval &OrigLI = LIS.getInterval(Original);