Make NumMicroOps a variable in the subtarget's instruction itinerary.

The TargetInstrInfo::getNumMicroOps API does not change, but soon it
will be used by MachineScheduler. Now each subtarget can specify the
number of micro-ops per itinerary class. For ARM, this is currently
always dynamic (-1), because it is used for load/store multiple which
depends on the number of register operands.

Zero is now a valid number of micro-ops. This can be used for
nop pseudo-instructions or instructions that the hardware can squash
during dispatch.

llvm-svn: 159406

1 files changed, 9 insertions, 9 deletions

diff --git a/llvm/lib/Target/ARM/ARMBaseInstrInfo.cpp b/llvm/lib/Target/ARM/ARMBaseInstrInfo.cpp
index 3a180dfa279..b3fef290931 100644
--- a/llvm/lib/Target/ARM/ARMBaseInstrInfo.cpp
+++ b/llvm/lib/Target/ARM/ARMBaseInstrInfo.cpp
@@ -2176,9 +2176,9 @@ ARMBaseInstrInfo::getNumMicroOps(const InstrItineraryData *ItinData,
 
   const MCInstrDesc &Desc = MI->getDesc();
   unsigned Class = Desc.getSchedClass();
-  unsigned UOps = ItinData->Itineraries[Class].NumMicroOps;
-  if (UOps)
-    return UOps;
+  int ItinUOps = ItinData->Itineraries[Class].NumMicroOps;
+  if (ItinUOps >= 0)
+    return ItinUOps;
 
   unsigned Opc = MI->getOpcode();
   switch (Opc) {
@@ -2252,19 +2252,19 @@ ARMBaseInstrInfo::getNumMicroOps(const InstrItineraryData *ItinData,
         return 2;
       // 4 registers would be issued: 2, 2.
       // 5 registers would be issued: 2, 2, 1.
-      UOps = (NumRegs / 2);
+      int A8UOps = (NumRegs / 2);
       if (NumRegs % 2)
-        ++UOps;
-      return UOps;
+        ++A8UOps;
+      return A8UOps;
     } else if (Subtarget.isCortexA9()) {
-      UOps = (NumRegs / 2);
+      int A9UOps = (NumRegs / 2);
       // If there are odd number of registers or if it's not 64-bit aligned,
       // then it takes an extra AGU (Address Generation Unit) cycle.
       if ((NumRegs % 2) ||
           !MI->hasOneMemOperand() ||
           (*MI->memoperands_begin())->getAlignment() < 8)
-        ++UOps;
-      return UOps;
+        ++A9UOps;
+      return A9UOps;
     } else {
       // Assume the worst.
       return NumRegs;