Add "hasSideEffects" method to MachineInstrInfo class.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@45126 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/include/llvm/Target/TargetInstrInfo.h b/include/llvm/Target/TargetInstrInfo.h
index 28a08b28bfdb114a9a9425bbebec55d70129001c..9b77649b796a988aafcf13fc007d75f00f0c3f1a 100644 (file)
--- a/include/llvm/Target/TargetInstrInfo.h
+++ b/include/llvm/Target/TargetInstrInfo.h
@@ -314,6 +314,15 @@ public:
            isReallyTriviallyReMaterializable(MI);
   }
 
+  /// hasSideEffects - Returns true if the instruction has side effects that are
+  /// not captured by any operands of the instruction or other flags.
+  bool hasSideEffects(MachineInstr *MI) const {
+    const TargetInstrDescriptor *TID = MI->getInstrDescriptor();
+    if (!(TID->Flags & M_NEVER_HAS_SIDE_EFFECTS ||
+          TID->Flags & M_MAY_HAVE_SIDE_EFFECTS)) return true;
+    if (TID->Flags & M_NEVER_HAS_SIDE_EFFECTS) return false;
+    return !isReallySideEffectFree(MI); // May have side effects
+  }
 protected:
   /// isReallyTriviallyReMaterializable - For instructions with opcodes for
   /// which the M_REMATERIALIZABLE flag is set, this function tests whether the
@@ -329,7 +338,7 @@ protected:
 
   /// isReallySideEffectFree - If the M_MAY_HAVE_SIDE_EFFECTS flag is set, this
   /// method is called to determine if the specific instance of this
-  /// instructions has side effects. This is useful in cases of instructions,
+  /// instruction has side effects. This is useful in cases of instructions,
   /// like loads, which generally always have side effects. A load from a
   /// constant pool doesn't have side effects, though. So we need to
   /// differentiate it from the general case.