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author | Dimitry Andric <dim@FreeBSD.org> | 2019-12-20 19:53:05 +0000 |
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committer | Dimitry Andric <dim@FreeBSD.org> | 2019-12-20 19:53:05 +0000 |
commit | 0b57cec536236d46e3dba9bd041533462f33dbb7 (patch) | |
tree | 56229dbdbbf76d18580f72f789003db17246c8d9 /contrib/llvm-project/llvm/lib/CodeGen/StackMapLivenessAnalysis.cpp | |
parent | 718ef55ec7785aae63f98f8ca05dc07ed399c16d (diff) | |
download | src-0b57cec536236d46e3dba9bd041533462f33dbb7.tar.gz src-0b57cec536236d46e3dba9bd041533462f33dbb7.zip |
Move all sources from the llvm project into contrib/llvm-project.
This uses the new layout of the upstream repository, which was recently
migrated to GitHub, and converted into a "monorepo". That is, most of
the earlier separate sub-projects with their own branches and tags were
consolidated into one top-level directory, and are now branched and
tagged together.
Updating the vendor area to match this layout is next.
Notes
Notes:
svn path=/head/; revision=355940
Diffstat (limited to 'contrib/llvm-project/llvm/lib/CodeGen/StackMapLivenessAnalysis.cpp')
-rw-r--r-- | contrib/llvm-project/llvm/lib/CodeGen/StackMapLivenessAnalysis.cpp | 170 |
1 files changed, 170 insertions, 0 deletions
diff --git a/contrib/llvm-project/llvm/lib/CodeGen/StackMapLivenessAnalysis.cpp b/contrib/llvm-project/llvm/lib/CodeGen/StackMapLivenessAnalysis.cpp new file mode 100644 index 000000000000..fb2abf3daa7f --- /dev/null +++ b/contrib/llvm-project/llvm/lib/CodeGen/StackMapLivenessAnalysis.cpp @@ -0,0 +1,170 @@ +//===-- StackMapLivenessAnalysis.cpp - StackMap live Out Analysis ----------===// +// +// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. +// See https://llvm.org/LICENSE.txt for license information. +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// +//===----------------------------------------------------------------------===// +// +// This file implements the StackMap Liveness analysis pass. The pass calculates +// the liveness for each basic block in a function and attaches the register +// live-out information to a stackmap or patchpoint intrinsic if present. +// +//===----------------------------------------------------------------------===// + +#include "llvm/ADT/Statistic.h" +#include "llvm/CodeGen/LivePhysRegs.h" +#include "llvm/CodeGen/MachineFrameInfo.h" +#include "llvm/CodeGen/MachineFunction.h" +#include "llvm/CodeGen/MachineFunctionPass.h" +#include "llvm/CodeGen/Passes.h" +#include "llvm/CodeGen/TargetSubtargetInfo.h" +#include "llvm/Support/CommandLine.h" +#include "llvm/Support/Debug.h" +#include "llvm/Support/raw_ostream.h" + +using namespace llvm; + +#define DEBUG_TYPE "stackmaps" + +static cl::opt<bool> EnablePatchPointLiveness( + "enable-patchpoint-liveness", cl::Hidden, cl::init(true), + cl::desc("Enable PatchPoint Liveness Analysis Pass")); + +STATISTIC(NumStackMapFuncVisited, "Number of functions visited"); +STATISTIC(NumStackMapFuncSkipped, "Number of functions skipped"); +STATISTIC(NumBBsVisited, "Number of basic blocks visited"); +STATISTIC(NumBBsHaveNoStackmap, "Number of basic blocks with no stackmap"); +STATISTIC(NumStackMaps, "Number of StackMaps visited"); + +namespace { +/// This pass calculates the liveness information for each basic block in +/// a function and attaches the register live-out information to a patchpoint +/// intrinsic if present. +/// +/// This pass can be disabled via the -enable-patchpoint-liveness=false flag. +/// The pass skips functions that don't have any patchpoint intrinsics. The +/// information provided by this pass is optional and not required by the +/// aformentioned intrinsic to function. +class StackMapLiveness : public MachineFunctionPass { + const TargetRegisterInfo *TRI; + LivePhysRegs LiveRegs; + +public: + static char ID; + + /// Default construct and initialize the pass. + StackMapLiveness(); + + /// Tell the pass manager which passes we depend on and what + /// information we preserve. + void getAnalysisUsage(AnalysisUsage &AU) const override; + + MachineFunctionProperties getRequiredProperties() const override { + return MachineFunctionProperties().set( + MachineFunctionProperties::Property::NoVRegs); + } + + /// Calculate the liveness information for the given machine function. + bool runOnMachineFunction(MachineFunction &MF) override; + +private: + /// Performs the actual liveness calculation for the function. + bool calculateLiveness(MachineFunction &MF); + + /// Add the current register live set to the instruction. + void addLiveOutSetToMI(MachineFunction &MF, MachineInstr &MI); + + /// Create a register mask and initialize it with the registers from + /// the register live set. + uint32_t *createRegisterMask(MachineFunction &MF) const; +}; +} // namespace + +char StackMapLiveness::ID = 0; +char &llvm::StackMapLivenessID = StackMapLiveness::ID; +INITIALIZE_PASS(StackMapLiveness, "stackmap-liveness", + "StackMap Liveness Analysis", false, false) + +/// Default construct and initialize the pass. +StackMapLiveness::StackMapLiveness() : MachineFunctionPass(ID) { + initializeStackMapLivenessPass(*PassRegistry::getPassRegistry()); +} + +/// Tell the pass manager which passes we depend on and what information we +/// preserve. +void StackMapLiveness::getAnalysisUsage(AnalysisUsage &AU) const { + // We preserve all information. + AU.setPreservesAll(); + AU.setPreservesCFG(); + MachineFunctionPass::getAnalysisUsage(AU); +} + +/// Calculate the liveness information for the given machine function. +bool StackMapLiveness::runOnMachineFunction(MachineFunction &MF) { + if (!EnablePatchPointLiveness) + return false; + + LLVM_DEBUG(dbgs() << "********** COMPUTING STACKMAP LIVENESS: " + << MF.getName() << " **********\n"); + TRI = MF.getSubtarget().getRegisterInfo(); + ++NumStackMapFuncVisited; + + // Skip this function if there are no patchpoints to process. + if (!MF.getFrameInfo().hasPatchPoint()) { + ++NumStackMapFuncSkipped; + return false; + } + return calculateLiveness(MF); +} + +/// Performs the actual liveness calculation for the function. +bool StackMapLiveness::calculateLiveness(MachineFunction &MF) { + bool HasChanged = false; + // For all basic blocks in the function. + for (auto &MBB : MF) { + LLVM_DEBUG(dbgs() << "****** BB " << MBB.getName() << " ******\n"); + LiveRegs.init(*TRI); + // FIXME: This should probably be addLiveOuts(). + LiveRegs.addLiveOutsNoPristines(MBB); + bool HasStackMap = false; + // Reverse iterate over all instructions and add the current live register + // set to an instruction if we encounter a patchpoint instruction. + for (auto I = MBB.rbegin(), E = MBB.rend(); I != E; ++I) { + if (I->getOpcode() == TargetOpcode::PATCHPOINT) { + addLiveOutSetToMI(MF, *I); + HasChanged = true; + HasStackMap = true; + ++NumStackMaps; + } + LLVM_DEBUG(dbgs() << " " << LiveRegs << " " << *I); + LiveRegs.stepBackward(*I); + } + ++NumBBsVisited; + if (!HasStackMap) + ++NumBBsHaveNoStackmap; + } + return HasChanged; +} + +/// Add the current register live set to the instruction. +void StackMapLiveness::addLiveOutSetToMI(MachineFunction &MF, + MachineInstr &MI) { + uint32_t *Mask = createRegisterMask(MF); + MachineOperand MO = MachineOperand::CreateRegLiveOut(Mask); + MI.addOperand(MF, MO); +} + +/// Create a register mask and initialize it with the registers from the +/// register live set. +uint32_t *StackMapLiveness::createRegisterMask(MachineFunction &MF) const { + // The mask is owned and cleaned up by the Machine Function. + uint32_t *Mask = MF.allocateRegMask(); + for (auto Reg : LiveRegs) + Mask[Reg / 32] |= 1U << (Reg % 32); + + // Give the target a chance to adjust the mask. + TRI->adjustStackMapLiveOutMask(Mask); + + return Mask; +} |