[WebAssembly] Fix updating/moving DBG_VALUEs in RegStackify
Summary:
As described in PR40209, there can be issues in DBG_VALUEs handling when multiple defs present in a BB. This patch
adds logic for detection of related to def DBG_VALUEs and localizes register update and movement to found DBG_VALUEs.
Reviewers: aheejin
Subscribers: mgorny, dschuff, sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D56401
llvm-svn: 351216
diff --git a/llvm/lib/Target/WebAssembly/WebAssemblyRegStackify.cpp b/llvm/lib/Target/WebAssembly/WebAssemblyRegStackify.cpp
index e991bf4..1eb32ed 100644
--- a/llvm/lib/Target/WebAssembly/WebAssemblyRegStackify.cpp
+++ b/llvm/lib/Target/WebAssembly/WebAssemblyRegStackify.cpp
@@ -22,6 +22,7 @@
#include "MCTargetDesc/WebAssemblyMCTargetDesc.h" // for WebAssembly::ARGUMENT_*
#include "WebAssembly.h"
+#include "WebAssemblyDebugValueManager.h"
#include "WebAssemblyMachineFunctionInfo.h"
#include "WebAssemblySubtarget.h"
#include "WebAssemblyUtilities.h"
@@ -466,27 +467,6 @@
}
}
-static void MoveDebugValues(unsigned Reg, MachineInstr *Insert,
- MachineBasicBlock &MBB, MachineRegisterInfo &MRI) {
- for (auto &Op : MRI.reg_operands(Reg)) {
- MachineInstr *MI = Op.getParent();
- assert(MI != nullptr);
- if (MI->isDebugValue() && MI->getParent() == &MBB)
- MBB.splice(Insert, &MBB, MI);
- }
-}
-
-static void UpdateDebugValuesReg(unsigned Reg, unsigned NewReg,
- MachineBasicBlock &MBB,
- MachineRegisterInfo &MRI) {
- for (auto &Op : MRI.reg_operands(Reg)) {
- MachineInstr *MI = Op.getParent();
- assert(MI != nullptr);
- if (MI->isDebugValue() && MI->getParent() == &MBB)
- Op.setReg(NewReg);
- }
-}
-
/// A single-use def in the same block with no intervening memory or register
/// dependencies; move the def down and nest it with the current instruction.
static MachineInstr *MoveForSingleUse(unsigned Reg, MachineOperand &Op,
@@ -496,8 +476,9 @@
MachineRegisterInfo &MRI) {
LLVM_DEBUG(dbgs() << "Move for single use: "; Def->dump());
+ WebAssemblyDebugValueManager DefDIs(Def);
MBB.splice(Insert, &MBB, Def);
- MoveDebugValues(Reg, Insert, MBB, MRI);
+ DefDIs.move(Insert);
LIS.handleMove(*Def);
if (MRI.hasOneDef(Reg) && MRI.hasOneUse(Reg)) {
@@ -522,7 +503,7 @@
MFI.stackifyVReg(NewReg);
- UpdateDebugValuesReg(Reg, NewReg, MBB, MRI);
+ DefDIs.updateReg(NewReg);
LLVM_DEBUG(dbgs() << " - Replaced register: "; Def->dump());
}
@@ -531,29 +512,6 @@
return Def;
}
-static void CloneDebugValues(unsigned Reg, MachineInstr *Insert,
- unsigned TargetReg, MachineBasicBlock &MBB,
- MachineRegisterInfo &MRI,
- const WebAssemblyInstrInfo *TII) {
- SmallPtrSet<MachineInstr *, 4> Instrs;
- for (auto &Op : MRI.reg_operands(Reg)) {
- MachineInstr *MI = Op.getParent();
- assert(MI != nullptr);
- if (MI->isDebugValue() && MI->getParent() == &MBB &&
- Instrs.find(MI) == Instrs.end())
- Instrs.insert(MI);
- }
- for (const auto &MI : Instrs) {
- MachineInstr &Clone = TII->duplicate(MBB, Insert, *MI);
- for (unsigned i = 0, e = Clone.getNumOperands(); i != e; ++i) {
- MachineOperand &MO = Clone.getOperand(i);
- if (MO.isReg() && MO.getReg() == Reg)
- MO.setReg(TargetReg);
- }
- LLVM_DEBUG(dbgs() << " - - Cloned DBG_VALUE: "; Clone.dump());
- }
-}
-
/// A trivially cloneable instruction; clone it and nest the new copy with the
/// current instruction.
static MachineInstr *RematerializeCheapDef(
@@ -564,6 +522,8 @@
LLVM_DEBUG(dbgs() << "Rematerializing cheap def: "; Def.dump());
LLVM_DEBUG(dbgs() << " - for use in "; Op.getParent()->dump());
+ WebAssemblyDebugValueManager DefDIs(&Def);
+
unsigned NewReg = MRI.createVirtualRegister(MRI.getRegClass(Reg));
TII->reMaterialize(MBB, Insert, NewReg, 0, Def, *TRI);
Op.setReg(NewReg);
@@ -593,10 +553,10 @@
LIS.RemoveMachineInstrFromMaps(Def);
Def.eraseFromParent();
- MoveDebugValues(Reg, &*Insert, MBB, MRI);
- UpdateDebugValuesReg(Reg, NewReg, MBB, MRI);
+ DefDIs.move(&*Insert);
+ DefDIs.updateReg(NewReg);
} else {
- CloneDebugValues(Reg, &*Insert, NewReg, MBB, MRI, TII);
+ DefDIs.clone(&*Insert, NewReg);
}
return Clone;
@@ -628,6 +588,8 @@
MachineRegisterInfo &MRI, const WebAssemblyInstrInfo *TII) {
LLVM_DEBUG(dbgs() << "Move and tee for multi-use:"; Def->dump());
+ WebAssemblyDebugValueManager DefDIs(Def);
+
// Move Def into place.
MBB.splice(Insert, &MBB, Def);
LIS.handleMove(*Def);
@@ -646,7 +608,7 @@
SlotIndex TeeIdx = LIS.InsertMachineInstrInMaps(*Tee).getRegSlot();
SlotIndex DefIdx = LIS.getInstructionIndex(*Def).getRegSlot();
- MoveDebugValues(Reg, Insert, MBB, MRI);
+ DefDIs.move(Insert);
// Tell LiveIntervals we moved the original vreg def from Def to Tee.
LiveInterval &LI = LIS.getInterval(Reg);
@@ -664,8 +626,8 @@
ImposeStackOrdering(Def);
ImposeStackOrdering(Tee);
- CloneDebugValues(Reg, Tee, DefReg, MBB, MRI, TII);
- CloneDebugValues(Reg, Insert, TeeReg, MBB, MRI, TII);
+ DefDIs.clone(Tee, DefReg);
+ DefDIs.clone(Insert, TeeReg);
LLVM_DEBUG(dbgs() << " - Replaced register: "; Def->dump());
LLVM_DEBUG(dbgs() << " - Tee instruction: "; Tee->dump());