Merge llvm trunk r321017 to contrib/llvm.

1 files changed, 95 insertions, 0 deletions

diff --git a/contrib/llvm/lib/Target/PowerPC/PPCPreEmitPeephole.cpp b/contrib/llvm/lib/Target/PowerPC/PPCPreEmitPeephole.cpp
new file mode 100644
index 000000000000..9501f0f89b81
--- /dev/null
+++ b/contrib/llvm/lib/Target/PowerPC/PPCPreEmitPeephole.cpp
@@ -0,0 +1,95 @@
+//===--------- PPCPreEmitPeephole.cpp - Late peephole optimizations -------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// A pre-emit peephole for catching opportunities introduced by late passes such
+// as MachineBlockPlacement.
+//
+//===----------------------------------------------------------------------===//
+
+#include "PPC.h"
+#include "PPCInstrInfo.h"
+#include "PPCSubtarget.h"
+#include "llvm/ADT/DenseMap.h"
+#include "llvm/ADT/Statistic.h"
+#include "llvm/CodeGen/LivePhysRegs.h"
+#include "llvm/CodeGen/MachineFunctionPass.h"
+#include "llvm/CodeGen/MachineInstrBuilder.h"
+#include "llvm/CodeGen/MachineRegisterInfo.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/ADT/Statistic.h"
+#include "llvm/Support/Debug.h"
+
+using namespace llvm;
+
+#define DEBUG_TYPE "ppc-pre-emit-peephole"
+
+STATISTIC(NumRRConvertedInPreEmit,
+          "Number of r+r instructions converted to r+i in pre-emit peephole");
+STATISTIC(NumRemovedInPreEmit,
+          "Number of instructions deleted in pre-emit peephole");
+
+static cl::opt<bool>
+RunPreEmitPeephole("ppc-late-peephole", cl::Hidden, cl::init(false),
+                   cl::desc("Run pre-emit peephole optimizations."));
+
+namespace {
+  class PPCPreEmitPeephole : public MachineFunctionPass {
+  public:
+    static char ID;
+    PPCPreEmitPeephole() : MachineFunctionPass(ID) {
+      initializePPCPreEmitPeepholePass(*PassRegistry::getPassRegistry());
+    }
+
+    void getAnalysisUsage(AnalysisUsage &AU) const override {
+      MachineFunctionPass::getAnalysisUsage(AU);
+    }
+
+    MachineFunctionProperties getRequiredProperties() const override {
+      return MachineFunctionProperties().set(
+          MachineFunctionProperties::Property::NoVRegs);
+    }
+
+    bool runOnMachineFunction(MachineFunction &MF) override {
+      if (skipFunction(MF.getFunction()) || !RunPreEmitPeephole)
+        return false;
+      bool Changed = false;
+      const PPCInstrInfo *TII = MF.getSubtarget<PPCSubtarget>().getInstrInfo();
+      SmallVector<MachineInstr *, 4> InstrsToErase;
+      for (MachineBasicBlock &MBB : MF) {
+        for (MachineInstr &MI : MBB) {
+          MachineInstr *DefMIToErase = nullptr;
+          if (TII->convertToImmediateForm(MI, &DefMIToErase)) {
+            Changed = true;
+            NumRRConvertedInPreEmit++;
+            DEBUG(dbgs() << "Converted instruction to imm form: ");
+            DEBUG(MI.dump());
+            if (DefMIToErase) {
+              InstrsToErase.push_back(DefMIToErase);
+            }
+          }
+        }
+      }
+      for (MachineInstr *MI : InstrsToErase) {
+        DEBUG(dbgs() << "PPC pre-emit peephole: erasing instruction: ");
+        DEBUG(MI->dump());
+        MI->eraseFromParent();
+        NumRemovedInPreEmit++;
+      }
+      return Changed;
+    }
+  };
+}
+
+INITIALIZE_PASS(PPCPreEmitPeephole, DEBUG_TYPE, "PowerPC Pre-Emit Peephole",
+                false, false)
+char PPCPreEmitPeephole::ID = 0;
+
+FunctionPass *llvm::createPPCPreEmitPeepholePass() {
+  return new PPCPreEmitPeephole();
+}