Disable some DAG combiner optimizations that may be

[oota-llvm.git] / lib / Target / Target.td

diff --git a/lib/Target/Target.td b/lib/Target/Target.td
index d7f1e38c118c181721feccd398edec72dc582f94..a268e164107f2f745aa2e2c1bba9a29ba77966e9 100644 (file)
--- a/lib/Target/Target.td
+++ b/lib/Target/Target.td
@@ -193,7 +193,6 @@ class Instruction {
   bit isSimpleLoad = 0;     // Is this just a load instruction?
   bit mayLoad      = 0;     // Is it possible for this inst to read memory?
   bit mayStore     = 0;     // Is it possible for this inst to write memory?
-  bit isImplicitDef = 0;    // Is this instruction an implicit def instruction?
   bit isTwoAddress = 0;     // Is this a two address instruction?
   bit isConvertibleToThreeAddress = 0;  // Can this 2-addr instruction promote?
   bit isCommutable = 0;     // Is this 3 operand instruction commutable?
@@ -204,22 +203,25 @@ class Instruction {
   bit usesCustomDAGSchedInserter = 0; // Pseudo instr needing special help.
   bit hasCtrlDep   = 0;     // Does this instruction r/w ctrl-flow chains?
   bit isNotDuplicable = 0;  // Is it unsafe to duplicate this instruction?
+  bit isAsCheapAsAMove = 0; // As cheap (or cheaper) than a move instruction.
 
   // Side effect flags - When set, the flags have these meanings:
   //
   //  hasSideEffects - The instruction has side effects that are not
   //    captured by any operands of the instruction or other flags.
+  //
   //  mayHaveSideEffects  - Some instances of the instruction can have side
   //    effects. The virtual method "isReallySideEffectFree" is called to
   //    determine this. Load instructions are an example of where this is
   //    useful. In general, loads always have side effects. However, loads from
   //    constant pools don't. Individual back ends make this determination.
+  //
   //  neverHasSideEffects - Set on an instruction with no pattern if it has no
   //    side effects.
   bit hasSideEffects = 0;
   bit mayHaveSideEffects = 0;
   bit neverHasSideEffects = 0;
-  
+
   InstrItinClass Itinerary = NoItinerary;// Execution steps used for scheduling.
 
   string Constraints = "";  // OperandConstraint, e.g. $src = $dst.
@@ -367,6 +369,7 @@ def INSERT_SUBREG : Instruction {
   let AsmString = "";
   let Namespace = "TargetInstrInfo";
   let neverHasSideEffects = 1;
+  let Constraints = "$supersrc = $dst";
 }
 def IMPLICIT_DEF : Instruction {
   let OutOperandList = (ops unknown:$dst);
@@ -375,6 +378,13 @@ def IMPLICIT_DEF : Instruction {
   let Namespace = "TargetInstrInfo";
   let neverHasSideEffects = 1;
 }
+def SUBREG_TO_REG : Instruction {
+  let OutOperandList = (ops unknown:$dst);
+  let InOperandList = (ops unknown:$implsrc, unknown:$subsrc, i32imm:$subidx);
+  let AsmString = "";
+  let Namespace = "TargetInstrInfo";
+  let neverHasSideEffects = 1;
+}
 
 //===----------------------------------------------------------------------===//
 // AsmWriter - This class can be implemented by targets that need to customize