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-rw-r--r--lib/CodeGen/MachineSink.cpp89
1 files changed, 52 insertions, 37 deletions
diff --git a/lib/CodeGen/MachineSink.cpp b/lib/CodeGen/MachineSink.cpp
index 79e3fea3f90c..bedfdd84b1ca 100644
--- a/lib/CodeGen/MachineSink.cpp
+++ b/lib/CodeGen/MachineSink.cpp
@@ -1,4 +1,4 @@
-//===-- MachineSink.cpp - Sinking for machine instructions ----------------===//
+//===- MachineSink.cpp - Sinking for machine instructions -----------------===//
//
// The LLVM Compiler Infrastructure
//
@@ -18,6 +18,7 @@
#include "llvm/ADT/SetVector.h"
#include "llvm/ADT/SmallSet.h"
+#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/SparseBitVector.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/Analysis/AliasAnalysis.h"
@@ -32,14 +33,17 @@
#include "llvm/CodeGen/MachineOperand.h"
#include "llvm/CodeGen/MachinePostDominators.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
-#include "llvm/CodeGen/Passes.h"
+#include "llvm/CodeGen/TargetInstrInfo.h"
+#include "llvm/CodeGen/TargetRegisterInfo.h"
+#include "llvm/CodeGen/TargetSubtargetInfo.h"
+#include "llvm/IR/BasicBlock.h"
#include "llvm/IR/LLVMContext.h"
+#include "llvm/IR/DebugInfoMetadata.h"
+#include "llvm/Pass.h"
+#include "llvm/Support/BranchProbability.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
-#include "llvm/Target/TargetInstrInfo.h"
-#include "llvm/Target/TargetRegisterInfo.h"
-#include "llvm/Target/TargetSubtargetInfo.h"
#include <algorithm>
#include <cassert>
#include <cstdint>
@@ -93,12 +97,12 @@ namespace {
// Remember which edges we are about to split.
// This is different from CEBCandidates since those edges
// will be split.
- SetVector<std::pair<MachineBasicBlock*, MachineBasicBlock*> > ToSplit;
+ SetVector<std::pair<MachineBasicBlock *, MachineBasicBlock *>> ToSplit;
SparseBitVector<> RegsToClearKillFlags;
- typedef std::map<MachineBasicBlock *, SmallVector<MachineBasicBlock *, 4>>
- AllSuccsCache;
+ using AllSuccsCache =
+ std::map<MachineBasicBlock *, SmallVector<MachineBasicBlock *, 4>>;
public:
static char ID; // Pass identification
@@ -133,6 +137,7 @@ namespace {
bool isWorthBreakingCriticalEdge(MachineInstr &MI,
MachineBasicBlock *From,
MachineBasicBlock *To);
+
/// \brief Postpone the splitting of the given critical
/// edge (\p From, \p To).
///
@@ -150,6 +155,7 @@ namespace {
MachineBasicBlock *To,
bool BreakPHIEdge);
bool SinkInstruction(MachineInstr &MI, bool &SawStore,
+
AllSuccsCache &AllSuccessors);
bool AllUsesDominatedByBlock(unsigned Reg, MachineBasicBlock *MBB,
MachineBasicBlock *DefMBB,
@@ -172,7 +178,9 @@ namespace {
} // end anonymous namespace
char MachineSinking::ID = 0;
+
char &llvm::MachineSinkingID = MachineSinking::ID;
+
INITIALIZE_PASS_BEGIN(MachineSinking, DEBUG_TYPE,
"Machine code sinking", false, false)
INITIALIZE_PASS_DEPENDENCY(MachineBranchProbabilityInfo)
@@ -236,17 +244,17 @@ MachineSinking::AllUsesDominatedByBlock(unsigned Reg,
// into and they are all PHI nodes. In this case, machine-sink must break
// the critical edge first. e.g.
//
- // BB#1: derived from LLVM BB %bb4.preheader
- // Predecessors according to CFG: BB#0
+ // %bb.1: derived from LLVM BB %bb4.preheader
+ // Predecessors according to CFG: %bb.0
// ...
- // %reg16385<def> = DEC64_32r %reg16437, %EFLAGS<imp-def,dead>
+ // %reg16385 = DEC64_32r %reg16437, implicit-def dead %eflags
// ...
- // JE_4 <BB#37>, %EFLAGS<imp-use>
- // Successors according to CFG: BB#37 BB#2
+ // JE_4 <%bb.37>, implicit %eflags
+ // Successors according to CFG: %bb.37 %bb.2
//
- // BB#2: derived from LLVM BB %bb.nph
- // Predecessors according to CFG: BB#0 BB#1
- // %reg16386<def> = PHI %reg16434, <BB#0>, %reg16385, <BB#1>
+ // %bb.2: derived from LLVM BB %bb.nph
+ // Predecessors according to CFG: %bb.0 %bb.1
+ // %reg16386 = PHI %reg16434, %bb.0, %reg16385, %bb.1
BreakPHIEdge = true;
for (MachineOperand &MO : MRI->use_nodbg_operands(Reg)) {
MachineInstr *UseInst = MO.getParent();
@@ -284,7 +292,7 @@ MachineSinking::AllUsesDominatedByBlock(unsigned Reg,
}
bool MachineSinking::runOnMachineFunction(MachineFunction &MF) {
- if (skipFunction(*MF.getFunction()))
+ if (skipFunction(MF.getFunction()))
return false;
DEBUG(dbgs() << "******** Machine Sinking ********\n");
@@ -314,10 +322,10 @@ bool MachineSinking::runOnMachineFunction(MachineFunction &MF) {
for (auto &Pair : ToSplit) {
auto NewSucc = Pair.first->SplitCriticalEdge(Pair.second, *this);
if (NewSucc != nullptr) {
- DEBUG(dbgs() << " *** Splitting critical edge:"
- " BB#" << Pair.first->getNumber()
- << " -- BB#" << NewSucc->getNumber()
- << " -- BB#" << Pair.second->getNumber() << '\n');
+ DEBUG(dbgs() << " *** Splitting critical edge: "
+ << printMBBReference(*Pair.first) << " -- "
+ << printMBBReference(*NewSucc) << " -- "
+ << printMBBReference(*Pair.second) << '\n');
MadeChange = true;
++NumSplit;
} else
@@ -453,33 +461,33 @@ bool MachineSinking::PostponeSplitCriticalEdge(MachineInstr &MI,
// It's not always legal to break critical edges and sink the computation
// to the edge.
//
- // BB#1:
+ // %bb.1:
// v1024
- // Beq BB#3
+ // Beq %bb.3
// <fallthrough>
- // BB#2:
+ // %bb.2:
// ... no uses of v1024
// <fallthrough>
- // BB#3:
+ // %bb.3:
// ...
// = v1024
//
- // If BB#1 -> BB#3 edge is broken and computation of v1024 is inserted:
+ // If %bb.1 -> %bb.3 edge is broken and computation of v1024 is inserted:
//
- // BB#1:
+ // %bb.1:
// ...
- // Bne BB#2
- // BB#4:
+ // Bne %bb.2
+ // %bb.4:
// v1024 =
- // B BB#3
- // BB#2:
+ // B %bb.3
+ // %bb.2:
// ... no uses of v1024
// <fallthrough>
- // BB#3:
+ // %bb.3:
// ...
// = v1024
//
- // This is incorrect since v1024 is not computed along the BB#1->BB#2->BB#3
+ // This is incorrect since v1024 is not computed along the %bb.1->%bb.2->%bb.3
// flow. We need to ensure the new basic block where the computation is
// sunk to dominates all the uses.
// It's only legal to break critical edge and sink the computation to the
@@ -570,7 +578,6 @@ bool MachineSinking::isProfitableToSinkTo(unsigned Reg, MachineInstr &MI,
SmallVector<MachineBasicBlock *, 4> &
MachineSinking::GetAllSortedSuccessors(MachineInstr &MI, MachineBasicBlock *MBB,
AllSuccsCache &AllSuccessors) const {
-
// Do we have the sorted successors in cache ?
auto Succs = AllSuccessors.find(MBB);
if (Succs != AllSuccessors.end())
@@ -711,7 +718,7 @@ MachineSinking::FindSuccToSinkTo(MachineInstr &MI, MachineBasicBlock *MBB,
static bool SinkingPreventsImplicitNullCheck(MachineInstr &MI,
const TargetInstrInfo *TII,
const TargetRegisterInfo *TRI) {
- typedef TargetInstrInfo::MachineBranchPredicate MachineBranchPredicate;
+ using MachineBranchPredicate = TargetInstrInfo::MachineBranchPredicate;
auto *MBB = MI.getParent();
if (MBB->pred_size() != 1)
@@ -784,7 +791,6 @@ bool MachineSinking::SinkInstruction(MachineInstr &MI, bool &SawStore,
if (!SuccToSinkTo)
return false;
-
// If the instruction to move defines a dead physical register which is live
// when leaving the basic block, don't move it because it could turn into a
// "zombie" define of that preg. E.g., EFLAGS. (<rdar://problem/8030636>)
@@ -863,11 +869,20 @@ bool MachineSinking::SinkInstruction(MachineInstr &MI, bool &SawStore,
SmallVector<MachineInstr *, 2> DbgValuesToSink;
collectDebugValues(MI, DbgValuesToSink);
+ // Merge or erase debug location to ensure consistent stepping in profilers
+ // and debuggers.
+ if (!SuccToSinkTo->empty() && InsertPos != SuccToSinkTo->end())
+ MI.setDebugLoc(DILocation::getMergedLocation(MI.getDebugLoc(),
+ InsertPos->getDebugLoc()));
+ else
+ MI.setDebugLoc(DebugLoc());
+
+
// Move the instruction.
SuccToSinkTo->splice(InsertPos, ParentBlock, MI,
++MachineBasicBlock::iterator(MI));
- // Move debug values.
+ // Move previously adjacent debug value instructions to the insert position.
for (SmallVectorImpl<MachineInstr *>::iterator DBI = DbgValuesToSink.begin(),
DBE = DbgValuesToSink.end(); DBI != DBE; ++DBI) {
MachineInstr *DbgMI = *DBI;
generated by cgit v1.2.3 (git 2.25.1) at 2024-10-27 20:24:46 +0000