[DebugInfo] Examine all uses of isDebugValue() for debug instructions.

Because we create a new kind of debug instruction, DBG_LABEL, we need to
check all passes which use isDebugValue() to check MachineInstr is debug
instruction or not. When expelling debug instructions, we should expel
both DBG_VALUE and DBG_LABEL. So, I create a new function,
isDebugInstr(), in MachineInstr to check whether the MachineInstr is
debug instruction or not.

This patch has no new test case. I have run regression test and there is
no difference in regression test.

Differential Revision: https://reviews.llvm.org/D45342

Patch by Hsiangkai Wang.

llvm-svn: 331844

1 files changed, 3 insertions, 0 deletions

diff --git a/llvm/lib/CodeGen/RegAllocFast.cpp b/llvm/lib/CodeGen/RegAllocFast.cpp
index 78b94a25210..241f680e2e8 100644
--- a/llvm/lib/CodeGen/RegAllocFast.cpp
+++ b/llvm/lib/CodeGen/RegAllocFast.cpp
@@ -910,6 +910,9 @@ void RegAllocFast::allocateBasicBlock(MachineBasicBlock &MBB) {
       continue;
     }
 
+    if (MI.isDebugLabel())
+      continue;
+
     // If this is a copy, we may be able to coalesce.
     unsigned CopySrcReg = 0;
     unsigned CopyDstReg = 0;