Thumb2 hazard recognizer.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106347 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/ARM/Thumb2HazardRecognizer.cpp b/lib/Target/ARM/Thumb2HazardRecognizer.cpp
new file mode 100644
index 0000000..1614422
--- /dev/null
+++ b/lib/Target/ARM/Thumb2HazardRecognizer.cpp
@@ -0,0 +1,50 @@
+//===-- Thumb2HazardRecognizer.cpp - Thumb2 postra hazard recognizer ------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "ARM.h"
+#include "Thumb2HazardRecognizer.h"
+#include "llvm/CodeGen/MachineInstr.h"
+#include "llvm/CodeGen/ScheduleDAG.h"
+using namespace llvm;
+
+ScheduleHazardRecognizer::HazardType
+Thumb2HazardRecognizer::getHazardType(SUnit *SU) {
+ if (ITBlockSize) {
+ MachineInstr *MI = SU->getInstr();
+ if (MI != ITBlockMIs[ITBlockSize-1])
+ return Hazard;
+ }
+
+ return PostRAHazardRecognizer::getHazardType(SU);
+}
+
+void Thumb2HazardRecognizer::Reset() {
+ ITBlockSize = 0;
+ PostRAHazardRecognizer::Reset();
+}
+
+void Thumb2HazardRecognizer::EmitInstruction(SUnit *SU) {
+ MachineInstr *MI = SU->getInstr();
+ unsigned Opcode = MI->getOpcode();
+ if (ITBlockSize) {
+ --ITBlockSize;
+ } else if (Opcode == ARM::t2IT) {
+ unsigned Mask = MI->getOperand(1).getImm();
+ unsigned NumTZ = CountTrailingZeros_32(Mask);
+ assert(NumTZ <= 3 && "Invalid IT mask!");
+ ITBlockSize = 4 - NumTZ;
+ MachineBasicBlock::iterator I = MI;
+ for (unsigned i = 0; i < ITBlockSize; ++i) {
+ ++I;
+ ITBlockMIs[ITBlockSize-1-i] = &*I;
+ }
+ }
+
+ PostRAHazardRecognizer::EmitInstruction(SU);
+}