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-rw-r--r--contrib/llvm/lib/Target/WebAssembly/WebAssemblyPrepareForLiveIntervals.cpp127
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diff --git a/contrib/llvm/lib/Target/WebAssembly/WebAssemblyPrepareForLiveIntervals.cpp b/contrib/llvm/lib/Target/WebAssembly/WebAssemblyPrepareForLiveIntervals.cpp
deleted file mode 100644
index 3bfbf607344d..000000000000
--- a/contrib/llvm/lib/Target/WebAssembly/WebAssemblyPrepareForLiveIntervals.cpp
+++ /dev/null
@@ -1,127 +0,0 @@
-//===- WebAssemblyPrepareForLiveIntervals.cpp - Prepare for LiveIntervals -===//
-//
-// 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
-//
-//===----------------------------------------------------------------------===//
-///
-/// \file
-/// Fix up code to meet LiveInterval's requirements.
-///
-/// Some CodeGen passes don't preserve LiveInterval's requirements, because
-/// they run after register allocation and it isn't important. However,
-/// WebAssembly runs LiveIntervals in a late pass. This pass transforms code
-/// to meet LiveIntervals' requirements; primarily, it ensures that all
-/// virtual register uses have definitions (IMPLICIT_DEF definitions if
-/// nothing else).
-///
-//===----------------------------------------------------------------------===//
-
-#include "MCTargetDesc/WebAssemblyMCTargetDesc.h"
-#include "WebAssembly.h"
-#include "WebAssemblyMachineFunctionInfo.h"
-#include "WebAssemblySubtarget.h"
-#include "WebAssemblyUtilities.h"
-#include "llvm/CodeGen/MachineFunctionPass.h"
-#include "llvm/CodeGen/MachineInstrBuilder.h"
-#include "llvm/CodeGen/MachineRegisterInfo.h"
-#include "llvm/CodeGen/Passes.h"
-#include "llvm/Support/Debug.h"
-#include "llvm/Support/raw_ostream.h"
-using namespace llvm;
-
-#define DEBUG_TYPE "wasm-prepare-for-live-intervals"
-
-namespace {
-class WebAssemblyPrepareForLiveIntervals final : public MachineFunctionPass {
-public:
- static char ID; // Pass identification, replacement for typeid
- WebAssemblyPrepareForLiveIntervals() : MachineFunctionPass(ID) {}
-
-private:
- StringRef getPassName() const override {
- return "WebAssembly Prepare For LiveIntervals";
- }
-
- void getAnalysisUsage(AnalysisUsage &AU) const override {
- AU.setPreservesCFG();
- MachineFunctionPass::getAnalysisUsage(AU);
- }
-
- bool runOnMachineFunction(MachineFunction &MF) override;
-};
-} // end anonymous namespace
-
-char WebAssemblyPrepareForLiveIntervals::ID = 0;
-INITIALIZE_PASS(WebAssemblyPrepareForLiveIntervals, DEBUG_TYPE,
- "Fix up code for LiveIntervals", false, false)
-
-FunctionPass *llvm::createWebAssemblyPrepareForLiveIntervals() {
- return new WebAssemblyPrepareForLiveIntervals();
-}
-
-// Test whether the given register has an ARGUMENT def.
-static bool hasArgumentDef(unsigned Reg, const MachineRegisterInfo &MRI) {
- for (const auto &Def : MRI.def_instructions(Reg))
- if (WebAssembly::isArgument(Def.getOpcode()))
- return true;
- return false;
-}
-
-bool WebAssemblyPrepareForLiveIntervals::runOnMachineFunction(
- MachineFunction &MF) {
- LLVM_DEBUG({
- dbgs() << "********** Prepare For LiveIntervals **********\n"
- << "********** Function: " << MF.getName() << '\n';
- });
-
- bool Changed = false;
- MachineRegisterInfo &MRI = MF.getRegInfo();
- const auto &TII = *MF.getSubtarget<WebAssemblySubtarget>().getInstrInfo();
- MachineBasicBlock &Entry = *MF.begin();
-
- assert(!mustPreserveAnalysisID(LiveIntervalsID) &&
- "LiveIntervals shouldn't be active yet!");
-
- // We don't preserve SSA form.
- MRI.leaveSSA();
-
- // BranchFolding and perhaps other passes don't preserve IMPLICIT_DEF
- // instructions. LiveIntervals requires that all paths to virtual register
- // uses provide a definition. Insert IMPLICIT_DEFs in the entry block to
- // conservatively satisfy this.
- //
- // TODO: This is fairly heavy-handed; find a better approach.
- //
- for (unsigned I = 0, E = MRI.getNumVirtRegs(); I < E; ++I) {
- unsigned Reg = TargetRegisterInfo::index2VirtReg(I);
-
- // Skip unused registers.
- if (MRI.use_nodbg_empty(Reg))
- continue;
-
- // Skip registers that have an ARGUMENT definition.
- if (hasArgumentDef(Reg, MRI))
- continue;
-
- BuildMI(Entry, Entry.begin(), DebugLoc(),
- TII.get(WebAssembly::IMPLICIT_DEF), Reg);
- Changed = true;
- }
-
- // Move ARGUMENT_* instructions to the top of the entry block, so that their
- // liveness reflects the fact that these really are live-in values.
- for (auto MII = Entry.begin(), MIE = Entry.end(); MII != MIE;) {
- MachineInstr &MI = *MII++;
- if (WebAssembly::isArgument(MI.getOpcode())) {
- MI.removeFromParent();
- Entry.insert(Entry.begin(), &MI);
- }
- }
-
- // Ok, we're now ready to run the LiveIntervals analysis again.
- MF.getProperties().set(MachineFunctionProperties::Property::TracksLiveness);
-
- return Changed;
-}