[NewPM][CodeGen] Introduce CodeGenPassBuilder to help build codegen pipeline

Following up on D67687.
Please refer to the RFC here http://lists.llvm.org/pipermail/llvm-dev/2020-July/143309.html

`CodeGenPassBuilder` is the NPM counterpart of `TargetPassConfig` with below differences.
- Debugging features (MIR print/verify, disable pass, start/stop-before/after, etc.) living in `TargetPassConfig` are moved to use PassInstrument as much as possible. (Implementation also lives in `TargetPassConfig.cpp`)
- `TargetPassConfig` is a polymorphic base (virtual inheritance) to build the target-dependent pipeline whereas `CodeGenPassBuilder` is the CRTP base/helper to implement the target-dependent pipeline. The motivation is flexibility for targets to customize the pipeline, inlining opportunity, and fits the overall NPM value semantics design.
- `TargetPassConfig` is a legacy immutable pass to declare hooks for targets to customize some target-independent codegen layer behavior. This is partially ported to TargetMachine::options. The rest, such as `createMachineScheduler/createPostMachineScheduler`, are left out for now. They should be implemented in LLVMTargetMachine in the future.

Reviewed By: arsenm

Differential Revision: https://reviews.llvm.org/D83608

1 files changed, 151 insertions, 10 deletions

diff --git a/llvm/lib/CodeGen/TargetPassConfig.cpp b/llvm/lib/CodeGen/TargetPassConfig.cpp
index 19db8eb..03a567e 100644
--- a/llvm/lib/CodeGen/TargetPassConfig.cpp
+++ b/llvm/lib/CodeGen/TargetPassConfig.cpp
@@ -22,6 +22,7 @@
 #include "llvm/Analysis/ScopedNoAliasAA.h"
 #include "llvm/Analysis/TargetTransformInfo.h"
 #include "llvm/Analysis/TypeBasedAliasAnalysis.h"
+#include "llvm/CodeGen/CGPassBuilderOption.h"
 #include "llvm/CodeGen/CSEConfigBase.h"
 #include "llvm/CodeGen/MachineFunctionPass.h"
 #include "llvm/CodeGen/MachinePassRegistry.h"
@@ -29,11 +30,13 @@
 #include "llvm/CodeGen/RegAllocRegistry.h"
 #include "llvm/IR/IRPrintingPasses.h"
 #include "llvm/IR/LegacyPassManager.h"
+#include "llvm/IR/PassInstrumentation.h"
 #include "llvm/IR/Verifier.h"
 #include "llvm/InitializePasses.h"
 #include "llvm/MC/MCAsmInfo.h"
 #include "llvm/MC/MCTargetOptions.h"
 #include "llvm/Pass.h"
+#include "llvm/Passes/StandardInstrumentations.h"
 #include "llvm/Support/CodeGen.h"
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Support/Compiler.h"
@@ -120,16 +123,17 @@ static cl::opt<cl::boolOrDefault> DebugifyAndStripAll(
         "Debugify MIR before and Strip debug after "
         "each pass except those known to be unsafe when debug info is present"),
     cl::ZeroOrMore);
-enum RunOutliner { AlwaysOutline, NeverOutline, TargetDefault };
+
 // Enable or disable the MachineOutliner.
 static cl::opt<RunOutliner> EnableMachineOutliner(
     "enable-machine-outliner", cl::desc("Enable the machine outliner"),
-    cl::Hidden, cl::ValueOptional, cl::init(TargetDefault),
-    cl::values(clEnumValN(AlwaysOutline, "always",
+    cl::Hidden, cl::ValueOptional, cl::init(RunOutliner::TargetDefault),
+    cl::values(clEnumValN(RunOutliner::AlwaysOutline, "always",
                           "Run on all functions guaranteed to be beneficial"),
-               clEnumValN(NeverOutline, "never", "Disable all outlining"),
+               clEnumValN(RunOutliner::NeverOutline, "never",
+                          "Disable all outlining"),
                // Sentinel value for unspecified option.
-               clEnumValN(AlwaysOutline, "", "")));
+               clEnumValN(RunOutliner::AlwaysOutline, "", "")));
 // Enable or disable FastISel. Both options are needed, because
 // FastISel is enabled by default with -fast, and we wish to be
 // able to enable or disable fast-isel independently from -O0.
@@ -172,7 +176,6 @@ static cl::opt<bool> EarlyLiveIntervals("early-live-intervals", cl::Hidden,
     cl::desc("Run live interval analysis earlier in the pipeline"));
 
 // Experimental option to use CFL-AA in codegen
-enum class CFLAAType { None, Steensgaard, Andersen, Both };
 static cl::opt<CFLAAType> UseCFLAA(
     "use-cfl-aa-in-codegen", cl::init(CFLAAType::None), cl::Hidden,
     cl::desc("Enable the new, experimental CFL alias analysis in CodeGen"),
@@ -404,6 +407,143 @@ void TargetPassConfig::setStartStopPasses() {
   Started = (StartAfter == nullptr) && (StartBefore == nullptr);
 }
 
+CGPassBuilderOption llvm::getCGPassBuilderOption() {
+  CGPassBuilderOption Opt;
+
+#define SET_OPTION(Option)                                                     \
+  if (Option.getNumOccurrences())                                              \
+    Opt.Option = Option;
+
+  SET_OPTION(EnableFastISelOption)
+  SET_OPTION(EnableGlobalISelAbort)
+  SET_OPTION(EnableGlobalISelOption)
+  SET_OPTION(EnableIPRA)
+  SET_OPTION(OptimizeRegAlloc)
+  SET_OPTION(VerifyMachineCode)
+
+  Opt.EnableMachineOutliner = EnableMachineOutliner;
+  Opt.UseCFLAA = UseCFLAA;
+  Opt.PrintISelInput = PrintISelInput;
+  Opt.PrintGCInfo = PrintGCInfo;
+  Opt.EnablePostMachineSchedulerPass = MISchedPostRA;
+  Opt.EnableLiveIntervalsPass = EarlyLiveIntervals;
+  Opt.EnableMachineBlockPlacementStatsPass = EnableBlockPlacementStats;
+  Opt.EnableImplicitNullChecksPass = EnableImplicitNullChecks;
+  Opt.DisableLoopStrengthReducePass = DisableLSR;
+  Opt.DisableCodeGenPreparePass = DisableCGP;
+  Opt.DisableMergeICmpsPass = DisableMergeICmps;
+  Opt.DisablePartiallyInlineLibCallsPass = DisablePartialLibcallInlining;
+  Opt.DisableConstantHoistingPass = DisableConstantHoisting;
+  Opt.PrintAfterLSR = PrintLSR;
+
+  return Opt;
+}
+
+static void registerPartialPipelineCallback(PassInstrumentationCallbacks &PIC,
+                                            LLVMTargetMachine &LLVMTM) {
+  StringRef StartBefore;
+  StringRef StartAfter;
+  StringRef StopBefore;
+  StringRef StopAfter;
+
+  unsigned StartBeforeInstanceNum = 0;
+  unsigned StartAfterInstanceNum = 0;
+  unsigned StopBeforeInstanceNum = 0;
+  unsigned StopAfterInstanceNum = 0;
+
+  std::tie(StartBefore, StartBeforeInstanceNum) =
+      getPassNameAndInstanceNum(StartBeforeOpt);
+  std::tie(StartAfter, StartAfterInstanceNum) =
+      getPassNameAndInstanceNum(StartAfterOpt);
+  std::tie(StopBefore, StopBeforeInstanceNum) =
+      getPassNameAndInstanceNum(StopBeforeOpt);
+  std::tie(StopAfter, StopAfterInstanceNum) =
+      getPassNameAndInstanceNum(StopAfterOpt);
+
+  if (StartBefore.empty() && StartAfter.empty() && StopBefore.empty() &&
+      StopAfter.empty())
+    return;
+
+  std::tie(StartBefore, std::ignore) =
+      LLVMTM.getPassNameFromLegacyName(StartBefore);
+  std::tie(StartAfter, std::ignore) =
+      LLVMTM.getPassNameFromLegacyName(StartAfter);
+  std::tie(StopBefore, std::ignore) =
+      LLVMTM.getPassNameFromLegacyName(StopBefore);
+  std::tie(StopAfter, std::ignore) =
+      LLVMTM.getPassNameFromLegacyName(StopAfter);
+  if (!StartBefore.empty() && !StartAfter.empty())
+    report_fatal_error(Twine(StartBeforeOptName) + Twine(" and ") +
+                       Twine(StartAfterOptName) + Twine(" specified!"));
+  if (!StopBefore.empty() && !StopAfter.empty())
+    report_fatal_error(Twine(StopBeforeOptName) + Twine(" and ") +
+                       Twine(StopAfterOptName) + Twine(" specified!"));
+
+  PIC.registerBeforePassCallback(
+      [=, EnableCurrent = StartBefore.empty() && StartAfter.empty(),
+       EnableNext = Optional<bool>(), StartBeforeCount = 0u,
+       StartAfterCount = 0u, StopBeforeCount = 0u,
+       StopAfterCount = 0u](StringRef P, Any) mutable {
+        bool StartBeforePass = !StartBefore.empty() && P.contains(StartBefore);
+        bool StartAfterPass = !StartAfter.empty() && P.contains(StartAfter);
+        bool StopBeforePass = !StopBefore.empty() && P.contains(StopBefore);
+        bool StopAfterPass = !StopAfter.empty() && P.contains(StopAfter);
+
+        // Implement -start-after/-stop-after
+        if (EnableNext) {
+          EnableCurrent = *EnableNext;
+          EnableNext.reset();
+        }
+
+        // Using PIC.registerAfterPassCallback won't work because if this
+        // callback returns false, AfterPassCallback is also skipped.
+        if (StartAfterPass && StartAfterCount++ == StartAfterInstanceNum) {
+          assert(!EnableNext && "Error: assign to EnableNext more than once");
+          EnableNext = true;
+        }
+        if (StopAfterPass && StopAfterCount++ == StopAfterInstanceNum) {
+          assert(!EnableNext && "Error: assign to EnableNext more than once");
+          EnableNext = false;
+        }
+
+        if (StartBeforePass && StartBeforeCount++ == StartBeforeInstanceNum)
+          EnableCurrent = true;
+        if (StopBeforePass && StopBeforeCount++ == StopBeforeInstanceNum)
+          EnableCurrent = false;
+        return EnableCurrent;
+      });
+}
+
+void llvm::registerCodeGenCallback(PassInstrumentationCallbacks &PIC,
+                                   LLVMTargetMachine &LLVMTM) {
+
+  // Register a callback for disabling passes.
+  PIC.registerBeforePassCallback([](StringRef P, Any) {
+
+#define DISABLE_PASS(Option, Name)                                             \
+  if (Option && P.contains(#Name))                                             \
+    return false;
+    DISABLE_PASS(DisableBlockPlacement, MachineBlockPlacementPass)
+    DISABLE_PASS(DisableBranchFold, BranchFolderPass)
+    DISABLE_PASS(DisableCopyProp, MachineCopyPropagationPass)
+    DISABLE_PASS(DisableEarlyIfConversion, EarlyIfConverterPass)
+    DISABLE_PASS(DisableEarlyTailDup, EarlyTailDuplicatePass)
+    DISABLE_PASS(DisableMachineCSE, MachineCSEPass)
+    DISABLE_PASS(DisableMachineDCE, DeadMachineInstructionElimPass)
+    DISABLE_PASS(DisableMachineLICM, EarlyMachineLICMPass)
+    DISABLE_PASS(DisableMachineSink, MachineSinkingPass)
+    DISABLE_PASS(DisablePostRAMachineLICM, MachineLICMPass)
+    DISABLE_PASS(DisablePostRAMachineSink, PostRAMachineSinkingPass)
+    DISABLE_PASS(DisablePostRASched, PostRASchedulerPass)
+    DISABLE_PASS(DisableSSC, StackSlotColoringPass)
+    DISABLE_PASS(DisableTailDuplicate, TailDuplicatePass)
+
+    return true;
+  });
+
+  registerPartialPipelineCallback(PIC, LLVMTM);
+}
+
 // Out of line constructor provides default values for pass options and
 // registers all common codegen passes.
 TargetPassConfig::TargetPassConfig(LLVMTargetMachine &TM, PassManagerBase &pm)
@@ -1012,10 +1152,11 @@ void TargetPassConfig::addMachinePasses() {
   addPass(&LiveDebugValuesID, false);
 
   if (TM->Options.EnableMachineOutliner && getOptLevel() != CodeGenOpt::None &&
-      EnableMachineOutliner != NeverOutline) {
-    bool RunOnAllFunctions = (EnableMachineOutliner == AlwaysOutline);
-    bool AddOutliner = RunOnAllFunctions ||
-                       TM->Options.SupportsDefaultOutlining;
+      EnableMachineOutliner != RunOutliner::NeverOutline) {
+    bool RunOnAllFunctions =
+        (EnableMachineOutliner == RunOutliner::AlwaysOutline);
+    bool AddOutliner =
+        RunOnAllFunctions || TM->Options.SupportsDefaultOutlining;
     if (AddOutliner)
       addPass(createMachineOutlinerPass(RunOnAllFunctions));
   }