[llvm] 9886046 - [CodeView] Combine variable def ranges that are continuous.
Zequan Wu via llvm-commits
llvm-commits at lists.llvm.org
Fri May 20 12:12:20 PDT 2022
Author: Zequan Wu
Date: 2022-05-20T12:12:14-07:00
New Revision: 9886046289fa63d8acf7e50cef59122d4b6ccb1f
URL: https://github.com/llvm/llvm-project/commit/9886046289fa63d8acf7e50cef59122d4b6ccb1f
DIFF: https://github.com/llvm/llvm-project/commit/9886046289fa63d8acf7e50cef59122d4b6ccb1f.diff
LOG: [CodeView] Combine variable def ranges that are continuous.
It saves about 1.13% size for chrome.dll.pdb on chrome official build.
Reviewed By: rnk
Differential Revision: https://reviews.llvm.org/D125721
Added:
Modified:
llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp
llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.h
llvm/test/DebugInfo/COFF/pieces.ll
Removed:
################################################################################
diff --git a/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp b/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp
index ece4167c791c0..94166922cbac7 100644
--- a/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp
@@ -1242,9 +1242,9 @@ void CodeViewDebug::emitDebugInfoForFunction(const Function *GV,
OS.emitCVLinetableDirective(FI.FuncId, Fn, FI.End);
}
-CodeViewDebug::LocalVarDefRange
+CodeViewDebug::LocalVarDef
CodeViewDebug::createDefRangeMem(uint16_t CVRegister, int Offset) {
- LocalVarDefRange DR;
+ LocalVarDef DR;
DR.InMemory = -1;
DR.DataOffset = Offset;
assert(DR.DataOffset == Offset && "truncation");
@@ -1296,19 +1296,19 @@ void CodeViewDebug::collectVariableInfoFromMFTable(
"Frame offsets with a scalable component are not supported");
// Calculate the label ranges.
- LocalVarDefRange DefRange =
+ LocalVarDef DefRange =
createDefRangeMem(CVReg, FrameOffset.getFixed() + ExprOffset);
+ LocalVariable Var;
+ Var.DIVar = VI.Var;
+
for (const InsnRange &Range : Scope->getRanges()) {
const MCSymbol *Begin = getLabelBeforeInsn(Range.first);
const MCSymbol *End = getLabelAfterInsn(Range.second);
End = End ? End : Asm->getFunctionEnd();
- DefRange.Ranges.emplace_back(Begin, End);
+ Var.DefRanges[DefRange].emplace_back(Begin, End);
}
- LocalVariable Var;
- Var.DIVar = VI.Var;
- Var.DefRanges.emplace_back(std::move(DefRange));
if (Deref)
Var.UseReferenceType = true;
@@ -1367,24 +1367,18 @@ void CodeViewDebug::calculateRanges(
// We can only handle a register or an offseted load of a register.
if (Location->Register == 0 || Location->LoadChain.size() > 1)
continue;
- {
- LocalVarDefRange DR;
- DR.CVRegister = TRI->getCodeViewRegNum(Location->Register);
- DR.InMemory = !Location->LoadChain.empty();
- DR.DataOffset =
- !Location->LoadChain.empty() ? Location->LoadChain.back() : 0;
- if (Location->FragmentInfo) {
- DR.IsSubfield = true;
- DR.StructOffset = Location->FragmentInfo->OffsetInBits / 8;
- } else {
- DR.IsSubfield = false;
- DR.StructOffset = 0;
- }
- if (Var.DefRanges.empty() ||
- Var.DefRanges.back().isDifferentLocation(DR)) {
- Var.DefRanges.emplace_back(std::move(DR));
- }
+ LocalVarDef DR;
+ DR.CVRegister = TRI->getCodeViewRegNum(Location->Register);
+ DR.InMemory = !Location->LoadChain.empty();
+ DR.DataOffset =
+ !Location->LoadChain.empty() ? Location->LoadChain.back() : 0;
+ if (Location->FragmentInfo) {
+ DR.IsSubfield = true;
+ DR.StructOffset = Location->FragmentInfo->OffsetInBits / 8;
+ } else {
+ DR.IsSubfield = false;
+ DR.StructOffset = 0;
}
// Compute the label range.
@@ -1401,7 +1395,7 @@ void CodeViewDebug::calculateRanges(
// If the last range end is our begin, just extend the last range.
// Otherwise make a new range.
SmallVectorImpl<std::pair<const MCSymbol *, const MCSymbol *>> &R =
- Var.DefRanges.back().Ranges;
+ Var.DefRanges[DR];
if (!R.empty() && R.back().second == Begin)
R.back().second = End;
else
@@ -2814,7 +2808,9 @@ void CodeViewDebug::emitLocalVariable(const FunctionInfo &FI,
// records and on disk formats are described in SymbolRecords.h. BytePrefix
// should be big enough to hold all forms without memory allocation.
SmallString<20> BytePrefix;
- for (const LocalVarDefRange &DefRange : Var.DefRanges) {
+ for (const auto &Pair : Var.DefRanges) {
+ LocalVarDef DefRange = Pair.first;
+ const auto &Ranges = Pair.second;
BytePrefix.clear();
if (DefRange.InMemory) {
int Offset = DefRange.DataOffset;
@@ -2838,7 +2834,7 @@ void CodeViewDebug::emitLocalVariable(const FunctionInfo &FI,
: (EncFP == FI.EncodedLocalFramePtrReg))) {
DefRangeFramePointerRelHeader DRHdr;
DRHdr.Offset = Offset;
- OS.emitCVDefRangeDirective(DefRange.Ranges, DRHdr);
+ OS.emitCVDefRangeDirective(Ranges, DRHdr);
} else {
uint16_t RegRelFlags = 0;
if (DefRange.IsSubfield) {
@@ -2850,7 +2846,7 @@ void CodeViewDebug::emitLocalVariable(const FunctionInfo &FI,
DRHdr.Register = Reg;
DRHdr.Flags = RegRelFlags;
DRHdr.BasePointerOffset = Offset;
- OS.emitCVDefRangeDirective(DefRange.Ranges, DRHdr);
+ OS.emitCVDefRangeDirective(Ranges, DRHdr);
}
} else {
assert(DefRange.DataOffset == 0 && "unexpected offset into register");
@@ -2859,12 +2855,12 @@ void CodeViewDebug::emitLocalVariable(const FunctionInfo &FI,
DRHdr.Register = DefRange.CVRegister;
DRHdr.MayHaveNoName = 0;
DRHdr.OffsetInParent = DefRange.StructOffset;
- OS.emitCVDefRangeDirective(DefRange.Ranges, DRHdr);
+ OS.emitCVDefRangeDirective(Ranges, DRHdr);
} else {
DefRangeRegisterHeader DRHdr;
DRHdr.Register = DefRange.CVRegister;
DRHdr.MayHaveNoName = 0;
- OS.emitCVDefRangeDirective(DefRange.Ranges, DRHdr);
+ OS.emitCVDefRangeDirective(Ranges, DRHdr);
}
}
}
diff --git a/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.h b/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.h
index d1fc3cdccb207..16f0082723ed0 100644
--- a/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.h
+++ b/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.h
@@ -50,18 +50,8 @@ class MachineFunction;
/// Collects and handles line tables information in a CodeView format.
class LLVM_LIBRARY_VISIBILITY CodeViewDebug : public DebugHandlerBase {
- MCStreamer &OS;
- BumpPtrAllocator Allocator;
- codeview::GlobalTypeTableBuilder TypeTable;
-
- /// Whether to emit type record hashes into .debug$H.
- bool EmitDebugGlobalHashes = false;
-
- /// The codeview CPU type used by the translation unit.
- codeview::CPUType TheCPU;
-
- /// Represents the most general definition range.
- struct LocalVarDefRange {
+public:
+ struct LocalVarDef {
/// Indicates that variable data is stored in memory relative to the
/// specified register.
int InMemory : 1;
@@ -79,23 +69,40 @@ class LLVM_LIBRARY_VISIBILITY CodeViewDebug : public DebugHandlerBase {
/// location containing the data.
uint16_t CVRegister;
- /// Compares all location fields. This includes all fields except the label
- /// ranges.
- bool isDifferentLocation(LocalVarDefRange &O) {
- return InMemory != O.InMemory || DataOffset != O.DataOffset ||
- IsSubfield != O.IsSubfield || StructOffset != O.StructOffset ||
- CVRegister != O.CVRegister;
+ uint64_t static toOpaqueValue(const LocalVarDef DR) {
+ uint64_t Val = 0;
+ std::memcpy(&Val, &DR, sizeof(Val));
+ return Val;
}
- SmallVector<std::pair<const MCSymbol *, const MCSymbol *>, 1> Ranges;
+ LocalVarDef static createFromOpaqueValue(uint64_t Val) {
+ LocalVarDef DR;
+ std::memcpy(&DR, &Val, sizeof(Val));
+ return DR;
+ }
};
- static LocalVarDefRange createDefRangeMem(uint16_t CVRegister, int Offset);
+ static_assert(sizeof(uint64_t) == sizeof(LocalVarDef), "");
+
+private:
+ MCStreamer &OS;
+ BumpPtrAllocator Allocator;
+ codeview::GlobalTypeTableBuilder TypeTable;
+
+ /// Whether to emit type record hashes into .debug$H.
+ bool EmitDebugGlobalHashes = false;
+
+ /// The codeview CPU type used by the translation unit.
+ codeview::CPUType TheCPU;
+
+ static LocalVarDef createDefRangeMem(uint16_t CVRegister, int Offset);
/// Similar to DbgVariable in DwarfDebug, but not dwarf-specific.
struct LocalVariable {
const DILocalVariable *DIVar = nullptr;
- SmallVector<LocalVarDefRange, 1> DefRanges;
+ MapVector<LocalVarDef,
+ SmallVector<std::pair<const MCSymbol *, const MCSymbol *>, 1>>
+ DefRanges;
bool UseReferenceType = false;
};
@@ -493,6 +500,27 @@ class LLVM_LIBRARY_VISIBILITY CodeViewDebug : public DebugHandlerBase {
void beginInstruction(const MachineInstr *MI) override;
};
+template <> struct DenseMapInfo<CodeViewDebug::LocalVarDef> {
+
+ static inline CodeViewDebug::LocalVarDef getEmptyKey() {
+ return CodeViewDebug::LocalVarDef::createFromOpaqueValue(~0ULL);
+ }
+
+ static inline CodeViewDebug::LocalVarDef getTombstoneKey() {
+ return CodeViewDebug::LocalVarDef::createFromOpaqueValue(~0ULL - 1ULL);
+ }
+
+ static unsigned getHashValue(const CodeViewDebug::LocalVarDef &DR) {
+ return CodeViewDebug::LocalVarDef::toOpaqueValue(DR) * 37ULL;
+ }
+
+ static bool isEqual(const CodeViewDebug::LocalVarDef &LHS,
+ const CodeViewDebug::LocalVarDef &RHS) {
+ return CodeViewDebug::LocalVarDef::toOpaqueValue(LHS) ==
+ CodeViewDebug::LocalVarDef::toOpaqueValue(RHS);
+ }
+};
+
} // end namespace llvm
#endif // LLVM_LIB_CODEGEN_ASMPRINTER_CODEVIEWDEBUG_H
diff --git a/llvm/test/DebugInfo/COFF/pieces.ll b/llvm/test/DebugInfo/COFF/pieces.ll
index 76c330a996b2f..54e266c3d5975 100644
--- a/llvm/test/DebugInfo/COFF/pieces.ll
+++ b/llvm/test/DebugInfo/COFF/pieces.ll
@@ -114,10 +114,8 @@
; ASM: .asciz "loop_csr" # Function name
; ASM: .short 4414 # Record kind: S_LOCAL
; ASM: .asciz "o"
-; ASM: .cv_def_range [[oy_ox_start]] [[ox_start]], subfield_reg, 24, 0
-; ASM: .cv_def_range [[oy_ox_start]] [[oy_start]], subfield_reg, 23, 4
-; ASM: .cv_def_range [[ox_start]] [[loopskip_start]], subfield_reg, 24, 0
-; ASM: .cv_def_range [[oy_start]] [[loopskip_start]], subfield_reg, 23, 4
+; ASM: .cv_def_range [[oy_ox_start]] [[loopskip_start]], subfield_reg, 24, 0
+; ASM: .cv_def_range [[oy_ox_start]] [[loopskip_start]], subfield_reg, 23, 4
; OBJ-LABEL: GlobalProcIdSym {
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