vendor/llvm/llvm-trunk-r304149

1 files changed, 22 insertions, 13 deletions

diff --git a/include/llvm/CodeGen/MachineInstr.h b/include/llvm/CodeGen/MachineInstr.h
index e7e728c1be28..8d040beff7a6 100644
--- a/include/llvm/CodeGen/MachineInstr.h
+++ b/include/llvm/CodeGen/MachineInstr.h
@@ -826,26 +826,35 @@ public:
       getOperand(0).getSubReg() == getOperand(1).getSubReg();
   }
 
-  /// Return true if this is a transient instruction that is
-  /// either very likely to be eliminated during register allocation (such as
-  /// copy-like instructions), or if this instruction doesn't have an
-  /// execution-time cost.
+  /// Return true if this instruction doesn't produce any output in the form of
+  /// executable instructions.
+  bool isMetaInstruction() const {
+    switch (getOpcode()) {
+    default:
+      return false;
+    case TargetOpcode::IMPLICIT_DEF:
+    case TargetOpcode::KILL:
+    case TargetOpcode::CFI_INSTRUCTION:
+    case TargetOpcode::EH_LABEL:
+    case TargetOpcode::GC_LABEL:
+    case TargetOpcode::DBG_VALUE:
+      return true;
+    }
+  }
+
+  /// Return true if this is a transient instruction that is either very likely
+  /// to be eliminated during register allocation (such as copy-like
+  /// instructions), or if this instruction doesn't have an execution-time cost.
   bool isTransient() const {
-    switch(getOpcode()) {
-    default: return false;
+    switch (getOpcode()) {
+    default:
+      return isMetaInstruction();
     // Copy-like instructions are usually eliminated during register allocation.
     case TargetOpcode::PHI:
     case TargetOpcode::COPY:
     case TargetOpcode::INSERT_SUBREG:
     case TargetOpcode::SUBREG_TO_REG:
     case TargetOpcode::REG_SEQUENCE:
-    // Pseudo-instructions that don't produce any real output.
-    case TargetOpcode::IMPLICIT_DEF:
-    case TargetOpcode::KILL:
-    case TargetOpcode::CFI_INSTRUCTION:
-    case TargetOpcode::EH_LABEL:
-    case TargetOpcode::GC_LABEL:
-    case TargetOpcode::DBG_VALUE:
       return true;
     }
   }