Files
archived-llvm/include/llvm/MC/MCObjectFileInfo.h
Sean Eveson ab494c9385 [MC] Function stack size section.
Re applying after fixing issues in the diff, sorry for any painful conflicts/merges!

Original RFC: http://lists.llvm.org/pipermail/llvm-dev/2017-August/117028.html

This change adds a '.stack-size' section containing metadata on function stack sizes to output ELF files behind the new -stack-size-section flag. The section contains pairs of function symbol references (8 byte) and stack sizes (unsigned LEB128).

The contents of this section can be used to measure changes to stack sizes between different versions of the compiler or a source base. The advantage of having a section is that we can extract this information when examining binaries that we didn't build, and it allows users and tools easy access to that information just by referencing the binary.

There is a follow up change to add an option to clang.

Thanks.

Reviewers: hfinkel, MatzeB

Reviewed By: MatzeB

Subscribers: thegameg, asb, llvm-commits

Differential Revision: https://reviews.llvm.org/D39788

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@319430 91177308-0d34-0410-b5e6-96231b3b80d8
2017-11-30 13:05:14 +00:00

377 lines
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//===-- llvm/MC/MCObjectFileInfo.h - Object File Info -----------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file describes common object file formats.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_MC_MCOBJECTFILEINFO_H
#define LLVM_MC_MCOBJECTFILEINFO_H
#include "llvm/ADT/Triple.h"
#include "llvm/Support/CodeGen.h"
namespace llvm {
class MCContext;
class MCSection;
class MCObjectFileInfo {
protected:
/// True if .comm supports alignment. This is a hack for as long as we
/// support 10.4 Tiger, whose assembler doesn't support alignment on comm.
bool CommDirectiveSupportsAlignment;
/// True if target object file supports a weak_definition of constant 0 for an
/// omitted EH frame.
bool SupportsWeakOmittedEHFrame;
/// True if the target object file supports emitting a compact unwind section
/// without an associated EH frame section.
bool SupportsCompactUnwindWithoutEHFrame;
/// OmitDwarfIfHaveCompactUnwind - True if the target object file
/// supports having some functions with compact unwind and other with
/// dwarf unwind.
bool OmitDwarfIfHaveCompactUnwind;
/// PersonalityEncoding, LSDAEncoding, TTypeEncoding - Some encoding values
/// for EH.
unsigned PersonalityEncoding;
unsigned LSDAEncoding;
unsigned FDECFIEncoding;
unsigned TTypeEncoding;
/// Compact unwind encoding indicating that we should emit only an EH frame.
unsigned CompactUnwindDwarfEHFrameOnly;
/// Section directive for standard text.
MCSection *TextSection;
/// Section directive for standard data.
MCSection *DataSection;
/// Section that is default initialized to zero.
MCSection *BSSSection;
/// Section that is readonly and can contain arbitrary initialized data.
/// Targets are not required to have a readonly section. If they don't,
/// various bits of code will fall back to using the data section for
/// constants.
MCSection *ReadOnlySection;
/// If exception handling is supported by the target, this is the section the
/// Language Specific Data Area information is emitted to.
MCSection *LSDASection;
/// If exception handling is supported by the target and the target can
/// support a compact representation of the CIE and FDE, this is the section
/// to emit them into.
MCSection *CompactUnwindSection;
// Dwarf sections for debug info. If a target supports debug info, these must
// be set.
MCSection *DwarfAbbrevSection;
MCSection *DwarfInfoSection;
MCSection *DwarfLineSection;
MCSection *DwarfFrameSection;
MCSection *DwarfPubTypesSection;
const MCSection *DwarfDebugInlineSection;
MCSection *DwarfStrSection;
MCSection *DwarfLocSection;
MCSection *DwarfARangesSection;
MCSection *DwarfRangesSection;
MCSection *DwarfMacinfoSection;
// The pubnames section is no longer generated by default. The generation
// can be enabled by a compiler flag.
MCSection *DwarfPubNamesSection;
/// DWARF5 Experimental Debug Info Sections
/// DwarfAccelNamesSection, DwarfAccelObjCSection,
/// DwarfAccelNamespaceSection, DwarfAccelTypesSection -
/// If we use the DWARF accelerated hash tables then we want to emit these
/// sections.
MCSection *DwarfAccelNamesSection;
MCSection *DwarfAccelObjCSection;
MCSection *DwarfAccelNamespaceSection;
MCSection *DwarfAccelTypesSection;
// These are used for the Fission separate debug information files.
MCSection *DwarfInfoDWOSection;
MCSection *DwarfTypesDWOSection;
MCSection *DwarfAbbrevDWOSection;
MCSection *DwarfStrDWOSection;
MCSection *DwarfLineDWOSection;
MCSection *DwarfLocDWOSection;
MCSection *DwarfStrOffDWOSection;
/// The DWARF v5 string offset and address table sections.
MCSection *DwarfStrOffSection;
MCSection *DwarfAddrSection;
// These are for Fission DWP files.
MCSection *DwarfCUIndexSection;
MCSection *DwarfTUIndexSection;
/// Section for newer gnu pubnames.
MCSection *DwarfGnuPubNamesSection;
/// Section for newer gnu pubtypes.
MCSection *DwarfGnuPubTypesSection;
// Section for Swift AST
MCSection *DwarfSwiftASTSection;
MCSection *COFFDebugSymbolsSection;
MCSection *COFFDebugTypesSection;
/// Extra TLS Variable Data section.
///
/// If the target needs to put additional information for a TLS variable,
/// it'll go here.
MCSection *TLSExtraDataSection;
/// Section directive for Thread Local data. ELF, MachO, COFF, and Wasm.
MCSection *TLSDataSection; // Defaults to ".tdata".
/// Section directive for Thread Local uninitialized data.
///
/// Null if this target doesn't support a BSS section. ELF and MachO only.
MCSection *TLSBSSSection; // Defaults to ".tbss".
/// StackMap section.
MCSection *StackMapSection;
/// FaultMap section.
MCSection *FaultMapSection;
/// EH frame section.
///
/// It is initialized on demand so it can be overwritten (with uniquing).
MCSection *EHFrameSection;
/// Section containing metadata on function stack sizes.
MCSection *StackSizesSection;
// ELF specific sections.
MCSection *DataRelROSection;
MCSection *MergeableConst4Section;
MCSection *MergeableConst8Section;
MCSection *MergeableConst16Section;
MCSection *MergeableConst32Section;
// MachO specific sections.
/// Section for thread local structure information.
///
/// Contains the source code name of the variable, visibility and a pointer to
/// the initial value (.tdata or .tbss).
MCSection *TLSTLVSection; // Defaults to ".tlv".
/// Section for thread local data initialization functions.
const MCSection *TLSThreadInitSection; // Defaults to ".thread_init_func".
MCSection *CStringSection;
MCSection *UStringSection;
MCSection *TextCoalSection;
MCSection *ConstTextCoalSection;
MCSection *ConstDataSection;
MCSection *DataCoalSection;
MCSection *DataCommonSection;
MCSection *DataBSSSection;
MCSection *FourByteConstantSection;
MCSection *EightByteConstantSection;
MCSection *SixteenByteConstantSection;
MCSection *LazySymbolPointerSection;
MCSection *NonLazySymbolPointerSection;
MCSection *ThreadLocalPointerSection;
/// COFF specific sections.
MCSection *DrectveSection;
MCSection *PDataSection;
MCSection *XDataSection;
MCSection *SXDataSection;
public:
void InitMCObjectFileInfo(const Triple &TT, bool PIC, MCContext &ctx,
bool LargeCodeModel = false);
bool getSupportsWeakOmittedEHFrame() const {
return SupportsWeakOmittedEHFrame;
}
bool getSupportsCompactUnwindWithoutEHFrame() const {
return SupportsCompactUnwindWithoutEHFrame;
}
bool getOmitDwarfIfHaveCompactUnwind() const {
return OmitDwarfIfHaveCompactUnwind;
}
bool getCommDirectiveSupportsAlignment() const {
return CommDirectiveSupportsAlignment;
}
unsigned getPersonalityEncoding() const { return PersonalityEncoding; }
unsigned getLSDAEncoding() const { return LSDAEncoding; }
unsigned getFDEEncoding() const { return FDECFIEncoding; }
unsigned getTTypeEncoding() const { return TTypeEncoding; }
unsigned getCompactUnwindDwarfEHFrameOnly() const {
return CompactUnwindDwarfEHFrameOnly;
}
MCSection *getTextSection() const { return TextSection; }
MCSection *getDataSection() const { return DataSection; }
MCSection *getBSSSection() const { return BSSSection; }
MCSection *getReadOnlySection() const { return ReadOnlySection; }
MCSection *getLSDASection() const { return LSDASection; }
MCSection *getCompactUnwindSection() const { return CompactUnwindSection; }
MCSection *getDwarfAbbrevSection() const { return DwarfAbbrevSection; }
MCSection *getDwarfInfoSection() const { return DwarfInfoSection; }
MCSection *getDwarfLineSection() const { return DwarfLineSection; }
MCSection *getDwarfFrameSection() const { return DwarfFrameSection; }
MCSection *getDwarfPubNamesSection() const { return DwarfPubNamesSection; }
MCSection *getDwarfPubTypesSection() const { return DwarfPubTypesSection; }
MCSection *getDwarfGnuPubNamesSection() const {
return DwarfGnuPubNamesSection;
}
MCSection *getDwarfGnuPubTypesSection() const {
return DwarfGnuPubTypesSection;
}
const MCSection *getDwarfDebugInlineSection() const {
return DwarfDebugInlineSection;
}
MCSection *getDwarfStrSection() const { return DwarfStrSection; }
MCSection *getDwarfLocSection() const { return DwarfLocSection; }
MCSection *getDwarfARangesSection() const { return DwarfARangesSection; }
MCSection *getDwarfRangesSection() const { return DwarfRangesSection; }
MCSection *getDwarfMacinfoSection() const { return DwarfMacinfoSection; }
// DWARF5 Experimental Debug Info Sections
MCSection *getDwarfAccelNamesSection() const {
return DwarfAccelNamesSection;
}
MCSection *getDwarfAccelObjCSection() const { return DwarfAccelObjCSection; }
MCSection *getDwarfAccelNamespaceSection() const {
return DwarfAccelNamespaceSection;
}
MCSection *getDwarfAccelTypesSection() const {
return DwarfAccelTypesSection;
}
MCSection *getDwarfInfoDWOSection() const { return DwarfInfoDWOSection; }
MCSection *getDwarfTypesSection(uint64_t Hash) const;
MCSection *getDwarfTypesDWOSection() const { return DwarfTypesDWOSection; }
MCSection *getDwarfAbbrevDWOSection() const { return DwarfAbbrevDWOSection; }
MCSection *getDwarfStrDWOSection() const { return DwarfStrDWOSection; }
MCSection *getDwarfLineDWOSection() const { return DwarfLineDWOSection; }
MCSection *getDwarfLocDWOSection() const { return DwarfLocDWOSection; }
MCSection *getDwarfStrOffDWOSection() const { return DwarfStrOffDWOSection; }
MCSection *getDwarfStrOffSection() const { return DwarfStrOffSection; }
MCSection *getDwarfAddrSection() const { return DwarfAddrSection; }
MCSection *getDwarfCUIndexSection() const { return DwarfCUIndexSection; }
MCSection *getDwarfTUIndexSection() const { return DwarfTUIndexSection; }
MCSection *getDwarfSwiftASTSection() const { return DwarfSwiftASTSection; }
MCSection *getCOFFDebugSymbolsSection() const {
return COFFDebugSymbolsSection;
}
MCSection *getCOFFDebugTypesSection() const {
return COFFDebugTypesSection;
}
MCSection *getTLSExtraDataSection() const { return TLSExtraDataSection; }
const MCSection *getTLSDataSection() const { return TLSDataSection; }
MCSection *getTLSBSSSection() const { return TLSBSSSection; }
MCSection *getStackMapSection() const { return StackMapSection; }
MCSection *getFaultMapSection() const { return FaultMapSection; }
MCSection *getStackSizesSection() const { return StackSizesSection; }
// ELF specific sections.
MCSection *getDataRelROSection() const { return DataRelROSection; }
const MCSection *getMergeableConst4Section() const {
return MergeableConst4Section;
}
const MCSection *getMergeableConst8Section() const {
return MergeableConst8Section;
}
const MCSection *getMergeableConst16Section() const {
return MergeableConst16Section;
}
const MCSection *getMergeableConst32Section() const {
return MergeableConst32Section;
}
// MachO specific sections.
const MCSection *getTLSTLVSection() const { return TLSTLVSection; }
const MCSection *getTLSThreadInitSection() const {
return TLSThreadInitSection;
}
const MCSection *getCStringSection() const { return CStringSection; }
const MCSection *getUStringSection() const { return UStringSection; }
MCSection *getTextCoalSection() const { return TextCoalSection; }
const MCSection *getConstTextCoalSection() const {
return ConstTextCoalSection;
}
const MCSection *getConstDataSection() const { return ConstDataSection; }
const MCSection *getDataCoalSection() const { return DataCoalSection; }
const MCSection *getDataCommonSection() const { return DataCommonSection; }
MCSection *getDataBSSSection() const { return DataBSSSection; }
const MCSection *getFourByteConstantSection() const {
return FourByteConstantSection;
}
const MCSection *getEightByteConstantSection() const {
return EightByteConstantSection;
}
const MCSection *getSixteenByteConstantSection() const {
return SixteenByteConstantSection;
}
MCSection *getLazySymbolPointerSection() const {
return LazySymbolPointerSection;
}
MCSection *getNonLazySymbolPointerSection() const {
return NonLazySymbolPointerSection;
}
MCSection *getThreadLocalPointerSection() const {
return ThreadLocalPointerSection;
}
// COFF specific sections.
MCSection *getDrectveSection() const { return DrectveSection; }
MCSection *getPDataSection() const { return PDataSection; }
MCSection *getXDataSection() const { return XDataSection; }
MCSection *getSXDataSection() const { return SXDataSection; }
MCSection *getEHFrameSection() {
return EHFrameSection;
}
enum Environment { IsMachO, IsELF, IsCOFF, IsWasm };
Environment getObjectFileType() const { return Env; }
bool isPositionIndependent() const { return PositionIndependent; }
private:
Environment Env;
bool PositionIndependent;
MCContext *Ctx;
Triple TT;
void initMachOMCObjectFileInfo(const Triple &T);
void initELFMCObjectFileInfo(const Triple &T, bool Large);
void initCOFFMCObjectFileInfo(const Triple &T);
void initWasmMCObjectFileInfo(const Triple &T);
public:
const Triple &getTargetTriple() const { return TT; }
};
} // end namespace llvm
#endif