Never add a kill flag to a constrained physical register in a two-addr instruction.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@77906 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/MachineInstr.cpp b/lib/CodeGen/MachineInstr.cpp
index 4ac2896..006a10a 100644
--- a/lib/CodeGen/MachineInstr.cpp
+++ b/lib/CodeGen/MachineInstr.cpp
@@ -1041,6 +1041,9 @@
         if (MO.isKill())
           // The register is already marked kill.
           return true;
+        if (isPhysReg && isRegTiedToDefOperand(i))
+          // Two-address uses of physregs must not be marked kill.
+          return true;
         MO.setIsKill();
         Found = true;
       }
diff --git a/test/CodeGen/Blackfin/cmp-small-imm.ll b/test/CodeGen/Blackfin/cmp-small-imm.ll
index 7d87cb0..ed285a7 100644
--- a/test/CodeGen/Blackfin/cmp-small-imm.ll
+++ b/test/CodeGen/Blackfin/cmp-small-imm.ll
@@ -1,7 +1,4 @@
 ; RUN: llvm-as < %s | llc -march=bfin > %t
-; XFAIL: *
-; Assertion failed: (isUsed(Reg) && "Using an undefined register!")
-; function forward, file RegisterScavenging.cpp, line 259.
 
 define i1 @cmp3(i32 %A) {
 	%R = icmp uge i32 %A, 2
diff --git a/test/CodeGen/Blackfin/promote-setcc.ll b/test/CodeGen/Blackfin/promote-setcc.ll
index b686c54..5855325 100644
--- a/test/CodeGen/Blackfin/promote-setcc.ll
+++ b/test/CodeGen/Blackfin/promote-setcc.ll
@@ -1,7 +1,4 @@
 ; RUN: llvm-as < %s | llc -march=bfin > %t
-; XFAIL: *
-; Assertion failed: (isUsed(Reg) && "Using an undefined register!"),
-; function forward, file RegisterScavenging.cpp, line 259.
 
 ; The DAG combiner may sometimes create illegal i16 SETCC operations when run
 ; after LegalizeOps. Try to tease out all the optimizations in