Add MachineBlockFrequency analysis.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@135352 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/MachineBlockFrequency.cpp b/lib/CodeGen/MachineBlockFrequency.cpp
new file mode 100644
index 0000000..893a320
--- /dev/null
+++ b/lib/CodeGen/MachineBlockFrequency.cpp
@@ -0,0 +1,59 @@
+//====----- MachineBlockFrequency.cpp - Machine Block Frequency Analysis ----====//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// Loops should be simplified before this analysis.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/InitializePasses.h"
+#include "llvm/Analysis/BlockFrequencyImpl.h"
+#include "llvm/CodeGen/MachineBlockFrequency.h"
+#include "llvm/CodeGen/Passes.h"
+#include "llvm/CodeGen/MachineBranchProbabilityInfo.h"
+
+using namespace llvm;
+
+INITIALIZE_PASS_BEGIN(MachineBlockFrequency, "machine-block-freq",
+ "Machine Block Frequency Analysis", true, true)
+INITIALIZE_PASS_DEPENDENCY(MachineBranchProbabilityInfo)
+INITIALIZE_PASS_END(MachineBlockFrequency, "machine-block-freq",
+ "Machine Block Frequency Analysis", true, true)
+
+char MachineBlockFrequency::ID = 0;
+
+
+MachineBlockFrequency::MachineBlockFrequency() : MachineFunctionPass(ID) {
+ initializeMachineBlockFrequencyPass(*PassRegistry::getPassRegistry());
+ MBFI = new BlockFrequencyImpl<MachineBasicBlock, MachineFunction,
+ MachineBranchProbabilityInfo>();
+}
+
+MachineBlockFrequency::~MachineBlockFrequency() {
+ delete MBFI;
+}
+
+void MachineBlockFrequency::getAnalysisUsage(AnalysisUsage &AU) const {
+ AU.addRequired<MachineBranchProbabilityInfo>();
+ AU.setPreservesAll();
+}
+
+bool MachineBlockFrequency::runOnMachineFunction(MachineFunction &F) {
+ MachineBranchProbabilityInfo &MBPI = getAnalysis<MachineBranchProbabilityInfo>();
+ MBFI->doFunction(&F, &MBPI);
+ return false;
+}
+
+/// getblockFreq - Return block frequency. Never return 0, value must be
+/// positive. Please note that initial frequency is equal to 1024. It means that
+/// we should not rely on the value itself, but only on the comparison to the
+/// other block frequencies. We do this to avoid using of floating points.
+///
+uint32_t MachineBlockFrequency::getBlockFreq(MachineBasicBlock *MBB) {
+ return MBFI->getBlockFreq(MBB);
+}