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-rw-r--r--lib/CodeGen/AsmPrinter/AsmPrinter.cpp42
-rw-r--r--lib/CodeGen/AsmPrinter/DwarfDebug.cpp17
-rw-r--r--lib/CodeGen/AsmPrinter/DwarfException.cpp79
-rw-r--r--lib/CodeGen/AsmPrinter/DwarfPrinter.cpp16
-rw-r--r--lib/CodeGen/AsmPrinter/DwarfPrinter.h3
5 files changed, 109 insertions, 48 deletions
diff --git a/lib/CodeGen/AsmPrinter/AsmPrinter.cpp b/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
index fc0838459388b..bd2b1b61971a8 100644
--- a/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
+++ b/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
@@ -917,11 +917,10 @@ void AsmPrinter::EmitAlignment(unsigned NumBits, const GlobalValue *GV,
if (NumBits == 0) return; // No need to emit alignment.
- unsigned FillValue = 0;
if (getCurrentSection()->getKind().isText())
- FillValue = MAI->getTextAlignFillValue();
-
- OutStreamer.EmitValueToAlignment(1 << NumBits, FillValue, 1, 0);
+ OutStreamer.EmitCodeAlignment(1 << NumBits);
+ else
+ OutStreamer.EmitValueToAlignment(1 << NumBits, 0, 1, 0);
}
/// LowerConstant - Lower the specified LLVM Constant to an MCExpr.
@@ -1717,7 +1716,7 @@ void AsmPrinter::EmitBasicBlockStart(const MachineBasicBlock *MBB) const {
}
// Print the main label for the block.
- if (MBB->pred_empty() || MBB->isOnlyReachableByFallthrough()) {
+ if (MBB->pred_empty() || isBlockOnlyReachableByFallthrough(MBB)) {
if (VerboseAsm) {
// NOTE: Want this comment at start of line.
O << MAI->getCommentString() << " BB#" << MBB->getNumber() << ':';
@@ -1764,6 +1763,39 @@ void AsmPrinter::printOffset(int64_t Offset) const {
O << Offset;
}
+/// isBlockOnlyReachableByFallthough - Return true if the basic block has
+/// exactly one predecessor and the control transfer mechanism between
+/// the predecessor and this block is a fall-through.
+bool AsmPrinter::isBlockOnlyReachableByFallthrough(const MachineBasicBlock *MBB)
+ const {
+ // If this is a landing pad, it isn't a fall through. If it has no preds,
+ // then nothing falls through to it.
+ if (MBB->isLandingPad() || MBB->pred_empty())
+ return false;
+
+ // If there isn't exactly one predecessor, it can't be a fall through.
+ MachineBasicBlock::const_pred_iterator PI = MBB->pred_begin(), PI2 = PI;
+ ++PI2;
+ if (PI2 != MBB->pred_end())
+ return false;
+
+ // The predecessor has to be immediately before this block.
+ const MachineBasicBlock *Pred = *PI;
+
+ if (!Pred->isLayoutSuccessor(MBB))
+ return false;
+
+ // If the block is completely empty, then it definitely does fall through.
+ if (Pred->empty())
+ return true;
+
+ // Otherwise, check the last instruction.
+ const MachineInstr &LastInst = Pred->back();
+ return !LastInst.getDesc().isBarrier();
+}
+
+
+
GCMetadataPrinter *AsmPrinter::GetOrCreateGCPrinter(GCStrategy *S) {
if (!S->usesMetadata())
return 0;
diff --git a/lib/CodeGen/AsmPrinter/DwarfDebug.cpp b/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
index 5093dd9a9c11b..5ad1e5ea05096 100644
--- a/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
+++ b/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
@@ -238,7 +238,18 @@ public:
LIndex = DSI;
}
}
- setLastInsn(LastInsn);
+
+ unsigned CurrentLastInsnIndex = 0;
+ if (const MachineInstr *CL = getLastInsn())
+ CurrentLastInsnIndex = MIIndexMap[CL];
+ unsigned FIndex = MIIndexMap[getFirstInsn()];
+
+ // Set LastInsn as the last instruction for this scope only if
+ // it follows
+ // 1) this scope's first instruction and
+ // 2) current last instruction for this scope, if any.
+ if (LIndex >= CurrentLastInsnIndex && LIndex >= FIndex)
+ setLastInsn(LastInsn);
}
#ifndef NDEBUG
@@ -1166,7 +1177,9 @@ DIE *DwarfDebug::createSubprogramDIE(const DISubprogram &SP, bool MakeDecl) {
return SPDie;
SPDie = new DIE(dwarf::DW_TAG_subprogram);
- addString(SPDie, dwarf::DW_AT_name, dwarf::DW_FORM_string, SP.getName());
+ // Constructors and operators for anonymous aggregates do not have names.
+ if (!SP.getName().empty())
+ addString(SPDie, dwarf::DW_AT_name, dwarf::DW_FORM_string, SP.getName());
StringRef LinkageName = SP.getLinkageName();
if (!LinkageName.empty())
diff --git a/lib/CodeGen/AsmPrinter/DwarfException.cpp b/lib/CodeGen/AsmPrinter/DwarfException.cpp
index c6c59f5998568..2b08ba4ad31f0 100644
--- a/lib/CodeGen/AsmPrinter/DwarfException.cpp
+++ b/lib/CodeGen/AsmPrinter/DwarfException.cpp
@@ -638,18 +638,18 @@ void DwarfException::EmitExceptionTable() {
const unsigned LandingPadSize = SizeOfEncodedValue(dwarf::DW_EH_PE_udata4);
bool IsSJLJ = MAI->getExceptionHandlingType() == ExceptionHandling::SjLj;
bool HaveTTData = IsSJLJ ? (!TypeInfos.empty() || !FilterIds.empty()) : true;
- unsigned SizeSites;
+ unsigned CallSiteTableLength;
if (IsSJLJ)
- SizeSites = 0;
+ CallSiteTableLength = 0;
else
- SizeSites = CallSites.size() *
+ CallSiteTableLength = CallSites.size() *
(SiteStartSize + SiteLengthSize + LandingPadSize);
for (unsigned i = 0, e = CallSites.size(); i < e; ++i) {
- SizeSites += MCAsmInfo::getULEB128Size(CallSites[i].Action);
+ CallSiteTableLength += MCAsmInfo::getULEB128Size(CallSites[i].Action);
if (IsSJLJ)
- SizeSites += MCAsmInfo::getULEB128Size(i);
+ CallSiteTableLength += MCAsmInfo::getULEB128Size(i);
}
// Type infos.
@@ -698,7 +698,20 @@ void DwarfException::EmitExceptionTable() {
Asm->OutStreamer.SwitchSection(LSDASection);
Asm->EmitAlignment(2, 0, 0, false);
+ // Emit the LSDA.
O << "GCC_except_table" << SubprogramCount << ":\n";
+ EmitLabel("exception", SubprogramCount);
+
+ if (IsSJLJ) {
+ SmallString<16> LSDAName;
+ raw_svector_ostream(LSDAName) << MAI->getPrivateGlobalPrefix() <<
+ "_LSDA_" << Asm->getFunctionNumber();
+ O << LSDAName.str() << ":\n";
+ }
+
+ // Emit the LSDA header.
+ EmitEncodingByte(dwarf::DW_EH_PE_omit, "@LPStart");
+ EmitEncodingByte(TTypeEncoding, "@TType");
// The type infos need to be aligned. GCC does this by inserting padding just
// before the type infos. However, this changes the size of the exception
@@ -707,7 +720,7 @@ void DwarfException::EmitExceptionTable() {
// So by increasing the size by inserting padding, you may increase the number
// of bytes used for writing the size. If it increases, say by one byte, then
// you now need to output one less byte of padding to get the type infos
- // aligned. However this decreases the size of the exception table. This
+ // aligned. However this decreases the size of the exception table. This
// changes the value you have to output for the exception table size. Due to
// the variable length encoding, the number of bytes used for writing the
// length may decrease. If so, you then have to increase the amount of
@@ -716,41 +729,35 @@ void DwarfException::EmitExceptionTable() {
// We chose another solution: don't output padding inside the table like GCC
// does, instead output it before the table.
unsigned SizeTypes = TypeInfos.size() * TypeFormatSize;
- unsigned TyOffset = sizeof(int8_t) + // Call site format
- MCAsmInfo::getULEB128Size(SizeSites) + // Call site table length
- SizeSites + SizeActions + SizeTypes;
- unsigned TotalSize = sizeof(int8_t) + // LPStart format
- sizeof(int8_t) + // TType format
- (HaveTTData ?
- MCAsmInfo::getULEB128Size(TyOffset) : 0) + // TType base offset
- TyOffset;
+ unsigned CallSiteTableLengthSize =
+ MCAsmInfo::getULEB128Size(CallSiteTableLength);
+ unsigned TTypeBaseOffset =
+ sizeof(int8_t) + // Call site format
+ CallSiteTableLengthSize + // Call site table length size
+ CallSiteTableLength + // Call site table length
+ SizeActions + // Actions size
+ SizeTypes;
+ unsigned TTypeBaseOffsetSize = MCAsmInfo::getULEB128Size(TTypeBaseOffset);
+ unsigned TotalSize =
+ sizeof(int8_t) + // LPStart format
+ sizeof(int8_t) + // TType format
+ (HaveTTData ? TTypeBaseOffsetSize : 0) + // TType base offset size
+ TTypeBaseOffset; // TType base offset
unsigned SizeAlign = (4 - TotalSize) & 3;
- for (unsigned i = 0; i != SizeAlign; ++i) {
- Asm->EmitInt8(0);
- EOL("Padding");
- }
-
- EmitLabel("exception", SubprogramCount);
-
- if (IsSJLJ) {
- SmallString<16> LSDAName;
- raw_svector_ostream(LSDAName) << MAI->getPrivateGlobalPrefix() <<
- "_LSDA_" << Asm->getFunctionNumber();
- O << LSDAName.str() << ":\n";
+ if (HaveTTData) {
+ // Account for any extra padding that will be added to the call site table
+ // length.
+ EmitULEB128(TTypeBaseOffset, "@TType base offset", SizeAlign);
+ SizeAlign = 0;
}
- // Emit the header.
- EmitEncodingByte(dwarf::DW_EH_PE_omit, "@LPStart");
- EmitEncodingByte(TTypeEncoding, "@TType");
-
- if (HaveTTData)
- EmitULEB128(TyOffset, "@TType base offset");
-
// SjLj Exception handling
if (IsSJLJ) {
EmitEncodingByte(dwarf::DW_EH_PE_udata4, "Call site");
- EmitULEB128(SizeSites, "Call site table length");
+
+ // Add extra padding if it wasn't added to the TType base offset.
+ EmitULEB128(CallSiteTableLength, "Call site table length", SizeAlign);
// Emit the landing pad site information.
unsigned idx = 0;
@@ -791,7 +798,9 @@ void DwarfException::EmitExceptionTable() {
// Emit the landing pad call site table.
EmitEncodingByte(dwarf::DW_EH_PE_udata4, "Call site");
- EmitULEB128(SizeSites, "Call site table length");
+
+ // Add extra padding if it wasn't added to the TType base offset.
+ EmitULEB128(CallSiteTableLength, "Call site table length", SizeAlign);
for (SmallVectorImpl<CallSiteEntry>::const_iterator
I = CallSites.begin(), E = CallSites.end(); I != E; ++I) {
diff --git a/lib/CodeGen/AsmPrinter/DwarfPrinter.cpp b/lib/CodeGen/AsmPrinter/DwarfPrinter.cpp
index 1299d048e4be6..28ff0ebb93fc0 100644
--- a/lib/CodeGen/AsmPrinter/DwarfPrinter.cpp
+++ b/lib/CodeGen/AsmPrinter/DwarfPrinter.cpp
@@ -159,29 +159,35 @@ void DwarfPrinter::EmitSLEB128(int Value, const char *Desc) const {
Value >>= 7;
IsMore = Value != Sign || ((Byte ^ Sign) & 0x40) != 0;
if (IsMore) Byte |= 0x80;
-
Asm->OutStreamer.EmitIntValue(Byte, 1, /*addrspace*/0);
} while (IsMore);
}
/// EmitULEB128 - emit the specified signed leb128 value.
-void DwarfPrinter::EmitULEB128(unsigned Value, const char *Desc) const {
+void DwarfPrinter::EmitULEB128(unsigned Value, const char *Desc,
+ unsigned PadTo) const {
if (Asm->VerboseAsm && Desc)
Asm->OutStreamer.AddComment(Desc);
- if (MAI->hasLEB128()) {
+ if (MAI->hasLEB128() && PadTo == 0) {
O << "\t.uleb128\t" << Value;
Asm->OutStreamer.AddBlankLine();
return;
}
- // If we don't have .uleb128, emit as .bytes.
+ // If we don't have .uleb128 or we want to emit padding, emit as .bytes.
do {
unsigned char Byte = static_cast<unsigned char>(Value & 0x7f);
Value >>= 7;
- if (Value) Byte |= 0x80;
+ if (Value || PadTo != 0) Byte |= 0x80;
Asm->OutStreamer.EmitIntValue(Byte, 1, /*addrspace*/0);
} while (Value);
+
+ if (PadTo) {
+ if (PadTo > 1)
+ Asm->OutStreamer.EmitFill(PadTo - 1, 0x80/*fillval*/, 0/*addrspace*/);
+ Asm->OutStreamer.EmitFill(1, 0/*fillval*/, 0/*addrspace*/);
+ }
}
diff --git a/lib/CodeGen/AsmPrinter/DwarfPrinter.h b/lib/CodeGen/AsmPrinter/DwarfPrinter.h
index 73de398e35e56..bd715f21548ba 100644
--- a/lib/CodeGen/AsmPrinter/DwarfPrinter.h
+++ b/lib/CodeGen/AsmPrinter/DwarfPrinter.h
@@ -111,7 +111,8 @@ public:
void EmitSLEB128(int Value, const char *Desc) const;
/// EmitULEB128 - emit the specified unsigned leb128 value.
- void EmitULEB128(unsigned Value, const char *Desc = 0) const;
+ void EmitULEB128(unsigned Value, const char *Desc = 0,
+ unsigned PadTo = 0) const;
/// PrintLabelName - Print label name in form used by Dwarf writer.
generated by cgit v1.2.3 (git 2.25.1) at 2025-06-23 19:36:04 +0000