llvm-mc: MCStreamer cleanups. - Remove EmitLocalSymbol, this is unsupported for now.

- Switch Emit{CommonSymbol,Zerofill} to take alignment in bytes (for consistency).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@80484 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Daniel Dunbar 2009-08-30 06:17:16 +00:00
parent 7a1e924b9a
commit 7092c7e1dc
6 changed files with 48 additions and 71 deletions

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@ -31,7 +31,7 @@ namespace llvm {
/// MCStreamer - Streaming machine code generation interface. This interface
/// is intended to provide a programatic interface that is very similar to the
/// level that an assembler .s file provides. It has callbacks to emit bytes,
/// "emit directives", etc. The implementation of this interface retains
/// handle directives, etc. The implementation of this interface retains
/// state to know what the current section is etc.
///
/// There are multiple implementations of this interface: one for writing out
@ -73,6 +73,7 @@ namespace llvm {
/// CurSection - This is the current section code is being emitted to, it is
/// kept up to date by SwitchSection.
const MCSection *CurSection;
public:
virtual ~MCStreamer();
@ -80,17 +81,16 @@ namespace llvm {
/// @name Symbol & Section Management
/// @{
/// getCurrentSection - Return the current seciton that the streamer is
/// emitting code to.
const MCSection *getCurrentSection() const { return CurSection; }
/// SwitchSection - Set the current section where code is being emitted to
/// @param Section. This is required to update CurSection.
///
/// This corresponds to assembler directives like .section, .text, etc.
virtual void SwitchSection(const MCSection *Section) = 0;
/// getCurrentSection - Return the current seciton that the streamer is
/// emitting code to.
const MCSection *getCurrentSection() const { return CurSection; }
/// EmitLabel - Emit a label for @param Symbol into the current section.
///
@ -100,9 +100,6 @@ namespace llvm {
/// @param Symbol - The symbol to emit. A given symbol should only be
/// emitted as a label once, and symbols emitted as a label should never be
/// used in an assignment.
//
// FIXME: What to do about the current section? Should we get rid of the
// symbol section in the constructor and initialize it here?
virtual void EmitLabel(MCSymbol *Symbol) = 0;
/// EmitAssemblerFlag - Note in the output the specified @param Flag
@ -126,11 +123,6 @@ namespace llvm {
bool MakeAbsolute = false) = 0;
/// EmitSymbolAttribute - Add the given @param Attribute to @param Symbol.
//
// FIXME: This doesn't make much sense, could we just have attributes be on
// the symbol and make the printer smart enough to add the right symbols?
// This should work as long as the order of attributes in the file doesn't
// matter.
virtual void EmitSymbolAttribute(MCSymbol *Symbol,
SymbolAttr Attribute) = 0;
@ -140,37 +132,30 @@ namespace llvm {
/// @param DescValue - The value to set into the n_desc field.
virtual void EmitSymbolDesc(MCSymbol *Symbol, unsigned DescValue) = 0;
/// EmitLocalSymbol - Emit a local symbol of @param Value to @param Symbol.
///
/// @param Symbol - The local symbol being created.
/// @param Value - The value for the symbol.
virtual void EmitLocalSymbol(MCSymbol *Symbol, const MCValue &Value) = 0;
/// EmitCommonSymbol - Emit a common or local common symbol of @param Size
/// with the @param Pow2Alignment if non-zero.
/// EmitCommonSymbol - Emit a common or local common symbol.
///
/// @param Symbol - The common symbol to emit.
/// @param Size - The size of the common symbol.
/// @param Pow2Alignment - The alignment of the common symbol if non-zero.
/// @param ByteAlignment - The alignment of the symbol if
/// non-zero. This must be a power of 2 on some targets.
virtual void EmitCommonSymbol(MCSymbol *Symbol, unsigned Size,
unsigned Pow2Alignment) = 0;
unsigned ByteAlignment) = 0;
/// EmitZerofill - Emit a the zerofill section and possiblity a symbol, if
/// @param Symbol is non-NULL, for @param Size and with the @param
/// Pow2Alignment if non-zero.
/// EmitZerofill - Emit a the zerofill section and an option symbol.
///
/// @param Section - The zerofill section to create and or to put the symbol
/// @param Symbol - The zerofill symbol to emit, if non-NULL.
/// @param Size - The size of the zerofill symbol.
/// @param Pow2Alignment - The alignment of the zerofill symbol if non-zero.
/// @param ByteAlignment - The alignment of the zerofill symbol if
/// non-zero. This must be a power of 2 on some targets.
virtual void EmitZerofill(const MCSection *Section, MCSymbol *Symbol = 0,
unsigned Size = 0,unsigned Pow2Alignment = 0) = 0;
unsigned Size = 0,unsigned ByteAlignment = 0) = 0;
/// @}
/// @name Generating Data
/// @{
/// EmitBytes - Emit the bytes in @param Data into the output.
/// EmitBytes - Emit the bytes in \arg Data into the output.
///
/// This is used to implement assembler directives such as .byte, .ascii,
/// etc.

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@ -53,13 +53,11 @@ public:
virtual void EmitSymbolDesc(MCSymbol *Symbol, unsigned DescValue);
virtual void EmitLocalSymbol(MCSymbol *Symbol, const MCValue &Value);
virtual void EmitCommonSymbol(MCSymbol *Symbol, unsigned Size,
unsigned Pow2Alignment);
unsigned ByteAlignment);
virtual void EmitZerofill(const MCSection *Section, MCSymbol *Symbol = 0,
unsigned Size = 0, unsigned Pow2Alignment = 0);
unsigned Size = 0, unsigned ByteAlignment = 0);
virtual void EmitBytes(const StringRef &Data);
@ -173,21 +171,17 @@ void MCAsmStreamer::EmitSymbolDesc(MCSymbol *Symbol, unsigned DescValue) {
OS << ".desc" << ' ' << Symbol << ',' << DescValue << '\n';
}
void MCAsmStreamer::EmitLocalSymbol(MCSymbol *Symbol, const MCValue &Value) {
OS << ".lsym" << ' ' << Symbol << ',' << Value << '\n';
}
void MCAsmStreamer::EmitCommonSymbol(MCSymbol *Symbol, unsigned Size,
unsigned Pow2Alignment) {
unsigned ByteAlignment) {
OS << ".comm";
OS << ' ' << Symbol << ',' << Size;
if (Pow2Alignment != 0)
OS << ',' << Pow2Alignment;
if (ByteAlignment != 0)
OS << ',' << Log2_32(ByteAlignment);
OS << '\n';
}
void MCAsmStreamer::EmitZerofill(const MCSection *Section, MCSymbol *Symbol,
unsigned Size, unsigned Pow2Alignment) {
unsigned Size, unsigned ByteAlignment) {
// Note: a .zerofill directive does not switch sections.
OS << ".zerofill ";
@ -197,8 +191,8 @@ void MCAsmStreamer::EmitZerofill(const MCSection *Section, MCSymbol *Symbol,
if (Symbol != NULL) {
OS << ',' << Symbol << ',' << Size;
if (Pow2Alignment != 0)
OS << ',' << Pow2Alignment;
if (ByteAlignment != 0)
OS << ',' << Log2_32(ByteAlignment);
}
OS << '\n';
}

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@ -111,13 +111,11 @@ public:
virtual void EmitSymbolDesc(MCSymbol *Symbol, unsigned DescValue);
virtual void EmitLocalSymbol(MCSymbol *Symbol, const MCValue &Value);
virtual void EmitCommonSymbol(MCSymbol *Symbol, unsigned Size,
unsigned Pow2Alignment);
unsigned ByteAlignment);
virtual void EmitZerofill(const MCSection *Section, MCSymbol *Symbol = 0,
unsigned Size = 0, unsigned Pow2Alignment = 0);
unsigned Size = 0, unsigned ByteAlignment = 0);
virtual void EmitBytes(const StringRef &Data);
@ -266,24 +264,18 @@ void MCMachOStreamer::EmitSymbolDesc(MCSymbol *Symbol, unsigned DescValue) {
getSymbolData(*Symbol).setFlags(DescValue & SF_DescFlagsMask);
}
void MCMachOStreamer::EmitLocalSymbol(MCSymbol *Symbol, const MCValue &Value) {
// FIXME: Implement?
llvm_report_error("unsupported '.lsym' directive");
}
void MCMachOStreamer::EmitCommonSymbol(MCSymbol *Symbol, unsigned Size,
unsigned Pow2Alignment) {
unsigned ByteAlignment) {
// FIXME: Darwin 'as' does appear to allow redef of a .comm by itself.
assert(Symbol->isUndefined() && "Cannot define a symbol twice!");
MCSymbolData &SD = getSymbolData(*Symbol);
SD.setExternal(true);
SD.setCommon(Size, 1 << Pow2Alignment);
SD.setCommon(Size, ByteAlignment);
}
void MCMachOStreamer::EmitZerofill(const MCSection *Section, MCSymbol *Symbol,
unsigned Size, unsigned Pow2Alignment) {
unsigned ByteAlignment = 1 << Pow2Alignment;
unsigned Size, unsigned ByteAlignment) {
MCSectionData &SectData = getSectionData(*Section);
// The symbol may not be present, which only creates the section.
@ -296,7 +288,7 @@ void MCMachOStreamer::EmitZerofill(const MCSection *Section, MCSymbol *Symbol,
MCSymbolData &SD = getSymbolData(*Symbol);
MCFragment *F = new MCZeroFillFragment(Size, 1 << Pow2Alignment, &SectData);
MCFragment *F = new MCZeroFillFragment(Size, ByteAlignment, &SectData);
SD.setFragment(F);
Symbol->setSection(*Section);

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@ -41,13 +41,11 @@ namespace {
virtual void EmitSymbolDesc(MCSymbol *Symbol, unsigned DescValue) {}
virtual void EmitLocalSymbol(MCSymbol *Symbol, const MCValue &Value) {}
virtual void EmitCommonSymbol(MCSymbol *Symbol, unsigned Size,
unsigned Pow2Alignment) {}
unsigned ByteAlignment) {}
virtual void EmitZerofill(const MCSection *Section, MCSymbol *Symbol = 0,
unsigned Size = 0, unsigned Pow2Alignment = 0) {}
unsigned Size = 0, unsigned ByteAlignment = 0) {}
virtual void EmitBytes(const StringRef &Data) {}

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@ -1,5 +1,10 @@
# RUN: llvm-mc -triple i386-unknown-unknown %s | FileCheck %s
# FIXME: This is currently unsupported. If it turns out no one uses it, we
# should just rip it out.
# XFAIL: *
# CHECK: TEST0:
# CHECK: .lsym bar,foo
# CHECK: .lsym baz,3

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@ -1257,15 +1257,17 @@ bool AsmParser::ParseDirectiveComm(bool IsLocal) {
if (!Sym->isUndefined())
return Error(IDLoc, "invalid symbol redefinition");
// '.lcomm' is equivalent to '.zerofill'.
// Create the Symbol as a common or local common with Size and Pow2Alignment
if (IsLocal)
if (IsLocal) {
Out.EmitZerofill(getMachOSection("__DATA", "__bss",
MCSectionMachO::S_ZEROFILL, 0,
SectionKind()),
Sym, Size, Pow2Alignment);
else
Out.EmitCommonSymbol(Sym, Size, Pow2Alignment);
Sym, Size, 1 << Pow2Alignment);
return false;
}
Out.EmitCommonSymbol(Sym, Size, 1 << Pow2Alignment);
return false;
}
@ -1355,7 +1357,7 @@ bool AsmParser::ParseDirectiveDarwinZerofill() {
Out.EmitZerofill(getMachOSection(Segment, Section,
MCSectionMachO::S_ZEROFILL, 0,
SectionKind()),
Sym, Size, Pow2Alignment);
Sym, Size, 1 << Pow2Alignment);
return false;
}
@ -1426,10 +1428,11 @@ bool AsmParser::ParseDirectiveDarwinLsym() {
Lexer.Lex();
// Create the Sym with the value of the Expr
Out.EmitLocalSymbol(Sym, Expr);
return false;
// We don't currently support this directive.
//
// FIXME: Diagnostic location!
(void) Sym;
return TokError("directive '.lsym' is unsupported");
}
/// ParseDirectiveInclude