Fix pr3954.  The register scavenger asserts for inline assembly with
register destinations that are tied to source operands.  The
TargetInstrDescr::findTiedToSrcOperand method silently fails for inline
assembly.  The existing MachineInstr::isRegReDefinedByTwoAddr was very
close to doing what is needed, so this revision makes a few changes to
that method and also renames it to isRegTiedToUseOperand (for consistency
with the very similar isRegTiedToDefOperand and because it handles both
two-address instructions and inline assembly with tied registers).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@68714 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/RegAllocLocal.cpp b/lib/CodeGen/RegAllocLocal.cpp
index b965dc9..14346e9 100644
--- a/lib/CodeGen/RegAllocLocal.cpp
+++ b/lib/CodeGen/RegAllocLocal.cpp
@@ -633,7 +633,7 @@
           // Check if this is a two address instruction.  If so, then
           // the def does not kill the use.
           if (last->second.first == I &&
-              I->isRegReDefinedByTwoAddr(i))
+              I->isRegTiedToUseOperand(i))
             continue;
           
           MachineOperand& lastUD =