1//=== WebAssemblyPreLegalizerCombiner.cpp ---------------------------------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This pass does combining of machine instructions at the generic MI level,
10// before the legalizer.
11//
12//===----------------------------------------------------------------------===//
13
14#include "WebAssembly.h"
15#include "WebAssemblySubtarget.h"
16#include "llvm/CodeGen/GlobalISel/CSEInfo.h"
17#include "llvm/CodeGen/GlobalISel/Combiner.h"
18#include "llvm/CodeGen/GlobalISel/CombinerHelper.h"
19#include "llvm/CodeGen/GlobalISel/CombinerInfo.h"
20#include "llvm/CodeGen/GlobalISel/GIMatchTableExecutorImpl.h"
21#include "llvm/CodeGen/GlobalISel/GISelValueTracking.h"
22#include "llvm/CodeGen/GlobalISel/MachineIRBuilder.h"
23#include "llvm/CodeGen/MachineDominators.h"
24#include "llvm/CodeGen/MachineFunction.h"
25#include "llvm/CodeGen/MachineFunctionAnalysisManager.h"
26#include "llvm/CodeGen/MachineFunctionPass.h"
27#include "llvm/CodeGen/MachinePassManager.h"
28#include "llvm/CodeGen/TargetPassConfig.h"
29#include "llvm/IR/Analysis.h"
30#include "llvm/Support/ErrorHandling.h"
31#include "llvm/Target/TargetMachine.h"
32
33#define GET_GICOMBINER_DEPS
34#include "WebAssemblyGenPreLegalizeGICombiner.inc"
35#undef GET_GICOMBINER_DEPS
36
37#define DEBUG_TYPE "wasm-prelegalizer-combiner"
38
39using namespace llvm;
40
41namespace {
42
43#define GET_GICOMBINER_TYPES
44#include "WebAssemblyGenPreLegalizeGICombiner.inc"
45#undef GET_GICOMBINER_TYPES
46
47class WebAssemblyPreLegalizerCombinerImpl : public Combiner {
48protected:
49 const CombinerHelper Helper;
50 const WebAssemblyPreLegalizerCombinerImplRuleConfig &RuleConfig;
51 const WebAssemblySubtarget &STI;
52
53public:
54 WebAssemblyPreLegalizerCombinerImpl(
55 MachineFunction &MF, CombinerInfo &CInfo, GISelValueTracking &VT,
56 GISelCSEInfo *CSEInfo,
57 const WebAssemblyPreLegalizerCombinerImplRuleConfig &RuleConfig,
58 const WebAssemblySubtarget &STI, MachineDominatorTree *MDT,
59 const LegalizerInfo *LI);
60
61 static const char *getName() { return "WebAssembly00PreLegalizerCombiner"; }
62
63 bool tryCombineAll(MachineInstr &I) const override;
64
65private:
66#define GET_GICOMBINER_CLASS_MEMBERS
67#include "WebAssemblyGenPreLegalizeGICombiner.inc"
68#undef GET_GICOMBINER_CLASS_MEMBERS
69};
70
71#define GET_GICOMBINER_IMPL
72#include "WebAssemblyGenPreLegalizeGICombiner.inc"
73#undef GET_GICOMBINER_IMPL
74
75WebAssemblyPreLegalizerCombinerImpl::WebAssemblyPreLegalizerCombinerImpl(
76 MachineFunction &MF, CombinerInfo &CInfo, GISelValueTracking &VT,
77 GISelCSEInfo *CSEInfo,
78 const WebAssemblyPreLegalizerCombinerImplRuleConfig &RuleConfig,
79 const WebAssemblySubtarget &STI, MachineDominatorTree *MDT,
80 const LegalizerInfo *LI)
81 : Combiner(MF, CInfo, &VT, CSEInfo),
82 Helper(Observer, B, /*IsPreLegalize*/ true, &VT, MDT, LI),
83 RuleConfig(RuleConfig), STI(STI),
84#define GET_GICOMBINER_CONSTRUCTOR_INITS
85#include "WebAssemblyGenPreLegalizeGICombiner.inc"
86#undef GET_GICOMBINER_CONSTRUCTOR_INITS
87{
88}
89
90// Pass boilerplate
91// ================
92
93class WebAssemblyPreLegalizerCombinerLegacy : public MachineFunctionPass {
94public:
95 static char ID;
96
97 WebAssemblyPreLegalizerCombinerLegacy();
98
99 StringRef getPassName() const override {
100 return "WebAssemblyPreLegalizerCombiner";
101 }
102
103 bool runOnMachineFunction(MachineFunction &MF) override;
104
105 void getAnalysisUsage(AnalysisUsage &AU) const override;
106};
107} // end anonymous namespace
108
109void WebAssemblyPreLegalizerCombinerLegacy::getAnalysisUsage(
110 AnalysisUsage &AU) const {
111 AU.addRequired<TargetPassConfig>();
112 AU.setPreservesCFG();
113 getSelectionDAGFallbackAnalysisUsage(AU);
114 AU.addRequired<GISelValueTrackingAnalysisLegacy>();
115 AU.addPreserved<GISelValueTrackingAnalysisLegacy>();
116 AU.addRequired<MachineDominatorTreeWrapperPass>();
117 AU.addRequired<GISelCSEAnalysisWrapperPass>();
118 AU.addPreserved<GISelCSEAnalysisWrapperPass>();
119 MachineFunctionPass::getAnalysisUsage(AU);
120}
121
122WebAssemblyPreLegalizerCombinerLegacy::WebAssemblyPreLegalizerCombinerLegacy()
123 : MachineFunctionPass(ID) {}
124
125static bool runCombinerOnMachineFunction(
126 MachineFunction &MF, function_ref<GISelCSEInfo *()> GetCSEInfo,
127 function_ref<bool()> ShouldSkip, function_ref<GISelValueTracking *()> GetVT,
128 function_ref<MachineDominatorTree *()> GetMDT) {
129 if (MF.getProperties().hasFailedISel())
130 return false;
131
132 WebAssemblyPreLegalizerCombinerImplRuleConfig RuleConfig;
133 if (!RuleConfig.parseCommandLineOption())
134 reportFatalUsageError(reason: "Invalid rule identifier");
135
136 GISelCSEInfo *CSEInfo = GetCSEInfo();
137
138 const WebAssemblySubtarget &ST = MF.getSubtarget<WebAssemblySubtarget>();
139 const auto *LI = ST.getLegalizerInfo();
140
141 const Function &F = MF.getFunction();
142 bool EnableOpt =
143 MF.getTarget().getOptLevel() != CodeGenOptLevel::None && !ShouldSkip();
144 GISelValueTracking *VT = GetVT();
145 MachineDominatorTree *MDT = GetMDT();
146 CombinerInfo CInfo(/*AllowIllegalOps*/ true, /*ShouldLegalizeIllegal*/ false,
147 /*LegalizerInfo*/ nullptr, EnableOpt, F.hasOptSize(),
148 F.hasMinSize());
149 // Disable fixed-point iteration to reduce compile-time
150 CInfo.MaxIterations = 1;
151 CInfo.ObserverLvl = CombinerInfo::ObserverLevel::SinglePass;
152 // This is the first Combiner, so the input IR might contain dead
153 // instructions.
154 CInfo.EnableFullDCE = true;
155 WebAssemblyPreLegalizerCombinerImpl Impl(MF, CInfo, *VT, CSEInfo, RuleConfig,
156 ST, MDT, LI);
157 return Impl.combineMachineInstrs();
158}
159
160char WebAssemblyPreLegalizerCombinerLegacy::ID = 0;
161INITIALIZE_PASS_BEGIN(WebAssemblyPreLegalizerCombinerLegacy, DEBUG_TYPE,
162 "Combine WebAssembly machine instrs before legalization",
163 false, false)
164INITIALIZE_PASS_DEPENDENCY(TargetPassConfig)
165INITIALIZE_PASS_DEPENDENCY(GISelValueTrackingAnalysisLegacy)
166INITIALIZE_PASS_DEPENDENCY(GISelCSEAnalysisWrapperPass)
167INITIALIZE_PASS_END(WebAssemblyPreLegalizerCombinerLegacy, DEBUG_TYPE,
168 "Combine WebAssembly machine instrs before legalization",
169 false, false)
170
171FunctionPass *llvm::createWebAssemblyPreLegalizerCombinerLegacyPass() {
172 return new WebAssemblyPreLegalizerCombinerLegacy();
173}
174
175bool WebAssemblyPreLegalizerCombinerLegacy::runOnMachineFunction(
176 MachineFunction &MF) {
177 return runCombinerOnMachineFunction(
178 MF,
179 GetCSEInfo: [&]() {
180 TargetPassConfig &TPC = getAnalysis<TargetPassConfig>();
181 GISelCSEAnalysisWrapper &Wrapper =
182 getAnalysis<GISelCSEAnalysisWrapperPass>().getCSEWrapper();
183 return &Wrapper.get(CSEOpt: TPC.getCSEConfig());
184 },
185 ShouldSkip: [&]() { return skipFunction(F: MF.getFunction()); },
186 GetVT: [&]() {
187 return &getAnalysis<GISelValueTrackingAnalysisLegacy>().get(MF);
188 },
189 GetMDT: [&]() {
190 return &getAnalysis<MachineDominatorTreeWrapperPass>().getDomTree();
191 });
192}
193
194PreservedAnalyses
195WebAssemblyPreLegalizerCombinerPass::run(MachineFunction &MF,
196 MachineFunctionAnalysisManager &MFAM) {
197 bool Changed = runCombinerOnMachineFunction(
198 MF, GetCSEInfo: [&]() { return MFAM.getResult<GISelCSEAnalysis>(IR&: MF).get(); },
199 ShouldSkip: [&]() { return MF.getFunction().hasOptNone(); },
200 GetVT: [&]() { return &MFAM.getResult<GISelValueTrackingAnalysis>(IR&: MF); },
201 GetMDT: [&]() { return &MFAM.getResult<MachineDominatorTreeAnalysis>(IR&: MF); });
202 return Changed ? getMachineFunctionPassPreservedAnalyses()
203 .preserveSet<CFGAnalyses>()
204 : PreservedAnalyses::all();
205}
206