[llvm-commits] [llvm] r155239 - /llvm/trunk/lib/CodeGen/MachineInstr.cpp

[Jakob Stoklund Olesen]

Author: stoklund
Date: Fri Apr 20 16:45:33 2012
New Revision: 155239

URL: http://llvm.org/viewvc/llvm-project?rev=155239&view=rev
Log:
Print <def,read-undef> to avoid confusion.

The <undef> flag on a def operand only applies to partial register
redefinitions. Only print the flag when relevant, and print it as
<def,read-undef> to make it clearer what it means.

Modified:
    llvm/trunk/lib/CodeGen/MachineInstr.cpp

Modified: llvm/trunk/lib/CodeGen/MachineInstr.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/MachineInstr.cpp?rev=155239&r1=155238&r2=155239&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/MachineInstr.cpp (original)
+++ llvm/trunk/lib/CodeGen/MachineInstr.cpp Fri Apr 20 16:45:33 2012
@@ -255,6 +255,10 @@
           OS << "imp-";
         OS << "def";
         NeedComma = true;
+        // <def,read-undef> only makes sense when getSubReg() is set.
+        // Don't clutter the output otherwise.
+        if (isUndef() && getSubReg())
+          OS << ",read-undef";
       } else if (isImplicit()) {
           OS << "imp-use";
           NeedComma = true;
@@ -271,7 +275,7 @@
           OS << "dead";
           NeedComma = true;
         }
-        if (isUndef()) {
+        if (isUndef() && isUse()) {
           if (NeedComma) OS << ',';
           OS << "undef";
           NeedComma = true;