Simple delay slot filler pass.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12730 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 87 insertions, 0 deletions

diff --git a/lib/Target/Sparc/DelaySlotFiller.cpp b/lib/Target/Sparc/DelaySlotFiller.cpp
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+++ b/lib/Target/Sparc/DelaySlotFiller.cpp
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+//===-- DelaySlotFiller.cpp - SparcV8 delay slot filler -------------------===//
+// 
+//                     The LLVM Compiler Infrastructure
+//
+// This file was developed by the LLVM research group and is distributed under
+// the University of Illinois Open Source License. See LICENSE.TXT for details.
+// 
+//===----------------------------------------------------------------------===//
+//
+// Simple local delay slot filler for SparcV8 machine code
+//
+//===----------------------------------------------------------------------===//
+
+#include "SparcV8.h"
+#include "SparcV8InstrInfo.h"
+#include "llvm/Constants.h"
+#include "llvm/DerivedTypes.h"
+#include "llvm/Module.h"
+#include "llvm/Assembly/Writer.h"
+#include "llvm/CodeGen/MachineFunctionPass.h"
+#include "llvm/CodeGen/MachineConstantPool.h"
+#include "llvm/CodeGen/MachineInstr.h"
+#include "llvm/CodeGen/MachineInstrBuilder.h"
+#include "llvm/Target/TargetMachine.h"
+#include "llvm/Support/Mangler.h"
+#include "Support/Statistic.h"
+#include "Support/StringExtras.h"
+#include "Support/CommandLine.h"
+#include <cctype>
+using namespace llvm;
+
+namespace {
+  Statistic<> FilledSlots ("delayslotfiller", "Num. of delay slots filled");
+
+  struct Filler : public MachineFunctionPass {
+    /// Target machine description which we query for reg. names, data
+    /// layout, etc.
+    ///
+    TargetMachine &TM;
+
+    Filler (TargetMachine &tm) : TM (tm) { }
+
+    virtual const char *getPassName () const {
+      return "SparcV8 Delay Slot Filler";
+    }
+
+    bool runOnMachineBasicBlock (MachineBasicBlock &MBB);
+    bool runOnMachineFunction (MachineFunction &F) {
+      bool Changed = false;
+      for (MachineFunction::iterator FI = F.begin (), FE = F.end ();
+           FI != FE; ++FI)
+        Changed |= runOnMachineBasicBlock (*FI);
+      return Changed;
+    }
+
+  };
+} // end of anonymous namespace
+
+/// createSparcV8DelaySlotFillerPass - Returns a pass that fills in delay
+/// slots in SparcV8 MachineFunctions
+///
+FunctionPass *llvm::createSparcV8DelaySlotFillerPass (TargetMachine &tm) {
+  return new Filler (tm);
+}
+
+static bool hasDelaySlot (unsigned Opcode) {
+  switch (Opcode) {
+    case V8::CALL:
+    case V8::RETL:
+      return true;
+    default:
+      return false;
+  }
+}
+
+/// runOnMachineBasicBlock - Fill in delay slots for the given basic block.
+///
+bool Filler::runOnMachineBasicBlock (MachineBasicBlock &MBB) {
+  for (MachineBasicBlock::iterator I = MBB.begin (); I != MBB.end (); ++I)
+    if (hasDelaySlot (I->getOpcode ())) {
+      MachineBasicBlock::iterator J = I;
+      ++J;
+      MBB.insert (J, BuildMI (V8::NOP, 0));
+      ++FilledSlots;
+    }
+  return false;
+}