[llvm] r271102 - [MC] Support symbolic expressions in assembly directives
Petr Hosek via llvm-commits
llvm-commits at lists.llvm.org
Fri May 27 22:57:51 PDT 2016
Author: phosek
Date: Sat May 28 00:57:48 2016
New Revision: 271102
URL: http://llvm.org/viewvc/llvm-project?rev=271102&view=rev
Log:
[MC] Support symbolic expressions in assembly directives
This matches the behavior of GNU assembler which supports symbolic
expressions in absolute expressions used in assembly directives.
Differential Revision: http://reviews.llvm.org/D20752
Modified:
llvm/trunk/include/llvm/MC/MCObjectStreamer.h
llvm/trunk/include/llvm/MC/MCStreamer.h
llvm/trunk/lib/MC/MCAsmStreamer.cpp
llvm/trunk/lib/MC/MCObjectStreamer.cpp
llvm/trunk/lib/MC/MCParser/AsmParser.cpp
llvm/trunk/lib/MC/MCStreamer.cpp
llvm/trunk/test/MC/AsmParser/directive_fill.s
llvm/trunk/test/MC/AsmParser/directive_space.s
Modified: llvm/trunk/include/llvm/MC/MCObjectStreamer.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/MC/MCObjectStreamer.h?rev=271102&r1=271101&r2=271102&view=diff
==============================================================================
--- llvm/trunk/include/llvm/MC/MCObjectStreamer.h (original)
+++ llvm/trunk/include/llvm/MC/MCObjectStreamer.h Sat May 28 00:57:48 2016
@@ -141,6 +141,11 @@ public:
bool EmitRelocDirective(const MCExpr &Offset, StringRef Name,
const MCExpr *Expr, SMLoc Loc) override;
void EmitFill(uint64_t NumBytes, uint8_t FillValue) override;
+ void emitFill(const MCExpr &NumBytes, uint64_t FillValue,
+ SMLoc Loc = SMLoc()) override;
+ void emitFill(const MCExpr &NumValues, int64_t Size, int64_t Expr,
+ SMLoc Loc = SMLoc()) override;
+
void FinishImpl() override;
/// Emit the absolute difference between two symbols if possible.
Modified: llvm/trunk/include/llvm/MC/MCStreamer.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/MC/MCStreamer.h?rev=271102&r1=271101&r2=271102&view=diff
==============================================================================
--- llvm/trunk/include/llvm/MC/MCStreamer.h (original)
+++ llvm/trunk/include/llvm/MC/MCStreamer.h Sat May 28 00:57:48 2016
@@ -577,6 +577,28 @@ public:
/// This implements directives such as '.space'.
virtual void EmitFill(uint64_t NumBytes, uint8_t FillValue);
+ /// \brief Emit \p Size bytes worth of the value specified by \p FillValue.
+ ///
+ /// This is used to implement assembler directives such as .space or .skip.
+ ///
+ /// \param NumBytes - The number of bytes to emit.
+ /// \param FillValue - The value to use when filling bytes.
+ /// \param Loc - The location of the expression for error reporting.
+ virtual void emitFill(const MCExpr &NumBytes, uint64_t FillValue,
+ SMLoc Loc = SMLoc());
+
+ /// \brief Emit \p NumValues copies of \p Size bytes. Each \p Size bytes is
+ /// taken from the lowest order 4 bytes of \p Expr expression.
+ ///
+ /// This is used to implement assembler directives such as .fill.
+ ///
+ /// \param NumValues - The number of copies of \p Size bytes to emit.
+ /// \param Size - The size (in bytes) of each repeated value.
+ /// \param Expr - The expression from which \p Size bytes are used.
+ virtual void emitFill(uint64_t NumValues, int64_t Size, int64_t Expr);
+ virtual void emitFill(const MCExpr &NumValues, int64_t Size, int64_t Expr,
+ SMLoc Loc = SMLoc());
+
/// \brief Emit NumBytes worth of zeros.
/// This function properly handles data in virtual sections.
void EmitZeros(uint64_t NumBytes);
Modified: llvm/trunk/lib/MC/MCAsmStreamer.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/MC/MCAsmStreamer.cpp?rev=271102&r1=271101&r2=271102&view=diff
==============================================================================
--- llvm/trunk/lib/MC/MCAsmStreamer.cpp (original)
+++ llvm/trunk/lib/MC/MCAsmStreamer.cpp Sat May 28 00:57:48 2016
@@ -31,6 +31,7 @@
#include "llvm/Support/LEB128.h"
#include "llvm/Support/MathExtras.h"
#include "llvm/Support/Path.h"
+#include "llvm/Support/SourceMgr.h"
#include <cctype>
using namespace llvm;
@@ -178,6 +179,14 @@ public:
void EmitFill(uint64_t NumBytes, uint8_t FillValue) override;
+ void emitFill(const MCExpr &NumBytes, uint64_t FillValue,
+ SMLoc Loc = SMLoc()) override;
+
+ void emitFill(uint64_t NumValues, int64_t Size, int64_t Expr) override;
+
+ void emitFill(const MCExpr &NumValues, int64_t Size, int64_t Expr,
+ SMLoc Loc = SMLoc()) override;
+
void EmitValueToAlignment(unsigned ByteAlignment, int64_t Value = 0,
unsigned ValueSize = 1,
unsigned MaxBytesToEmit = 0) override;
@@ -799,16 +808,41 @@ void MCAsmStreamer::EmitGPRel32Value(con
void MCAsmStreamer::EmitFill(uint64_t NumBytes, uint8_t FillValue) {
if (NumBytes == 0) return;
+ const MCExpr *E = MCConstantExpr::create(NumBytes, getContext());
+ emitFill(*E, FillValue);
+}
+
+void MCAsmStreamer::emitFill(const MCExpr &NumBytes, uint64_t FillValue,
+ SMLoc Loc) {
if (const char *ZeroDirective = MAI->getZeroDirective()) {
- OS << ZeroDirective << NumBytes;
+ // FIXME: Emit location directives
+ OS << ZeroDirective;
+ NumBytes.print(OS, MAI);
if (FillValue != 0)
OS << ',' << (int)FillValue;
EmitEOL();
return;
}
- // Emit a byte at a time.
- MCStreamer::EmitFill(NumBytes, FillValue);
+ MCStreamer::emitFill(NumBytes, FillValue);
+}
+
+void MCAsmStreamer::emitFill(uint64_t NumValues, int64_t Size, int64_t Expr) {
+ if (NumValues == 0)
+ return;
+
+ const MCExpr *E = MCConstantExpr::create(NumValues, getContext());
+ emitFill(*E, Size, Expr);
+}
+
+void MCAsmStreamer::emitFill(const MCExpr &NumValues, int64_t Size,
+ int64_t Expr, SMLoc Loc) {
+ // FIXME: Emit location directives
+ OS << "\t.fill\t";
+ NumValues.print(OS, MAI);
+ OS << ", " << Size << ", 0x";
+ OS.write_hex(truncateToSize(Expr, 4));
+ EmitEOL();
}
void MCAsmStreamer::EmitValueToAlignment(unsigned ByteAlignment, int64_t Value,
Modified: llvm/trunk/lib/MC/MCObjectStreamer.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/MC/MCObjectStreamer.cpp?rev=271102&r1=271101&r2=271102&view=diff
==============================================================================
--- llvm/trunk/lib/MC/MCObjectStreamer.cpp (original)
+++ llvm/trunk/lib/MC/MCObjectStreamer.cpp Sat May 28 00:57:48 2016
@@ -20,6 +20,7 @@
#include "llvm/MC/MCSection.h"
#include "llvm/MC/MCSymbol.h"
#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/SourceMgr.h"
#include "llvm/Support/TargetRegistry.h"
using namespace llvm;
@@ -496,6 +497,43 @@ void MCObjectStreamer::EmitFill(uint64_t
insert(new MCFillFragment(FillValue, NumBytes));
}
+void MCObjectStreamer::emitFill(const MCExpr &NumBytes, uint64_t FillValue,
+ SMLoc Loc) {
+ MCDataFragment *DF = getOrCreateDataFragment();
+ flushPendingLabels(DF, DF->getContents().size());
+
+ int64_t IntNumBytes;
+ if (!NumBytes.evaluateAsAbsolute(IntNumBytes, getAssembler())) {
+ getContext().reportError(Loc, "expected absolute expression");
+ return;
+ }
+
+ if (IntNumBytes <= 0) {
+ getContext().reportError(Loc, "invalid number of bytes");
+ return;
+ }
+
+ EmitFill(IntNumBytes, FillValue);
+}
+
+void MCObjectStreamer::emitFill(const MCExpr &NumValues, int64_t Size,
+ int64_t Expr, SMLoc Loc) {
+ int64_t IntNumValues;
+ if (!NumValues.evaluateAsAbsolute(IntNumValues, getAssembler())) {
+ getContext().reportError(Loc, "expected absolute expression");
+ return;
+ }
+
+ if (IntNumValues < 0) {
+ getContext().getSourceManager()->PrintMessage(
+ Loc, SourceMgr::DK_Warning,
+ "'.fill' directive with negative repeat count has no effect");
+ return;
+ }
+
+ MCStreamer::emitFill(IntNumValues, Size, Expr);
+}
+
void MCObjectStreamer::FinishImpl() {
// If we are generating dwarf for assembly source files dump out the sections.
if (getContext().getGenDwarfForAssembly())
Modified: llvm/trunk/lib/MC/MCParser/AsmParser.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/MC/MCParser/AsmParser.cpp?rev=271102&r1=271101&r2=271102&view=diff
==============================================================================
--- llvm/trunk/lib/MC/MCParser/AsmParser.cpp (original)
+++ llvm/trunk/lib/MC/MCParser/AsmParser.cpp Sat May 28 00:57:48 2016
@@ -2738,8 +2738,9 @@ bool AsmParser::parseDirectiveRealValue(
bool AsmParser::parseDirectiveZero() {
checkForValidSection();
- int64_t NumBytes;
- if (parseAbsoluteExpression(NumBytes))
+ SMLoc NumBytesLoc = Lexer.getLoc();
+ const MCExpr *NumBytes;
+ if (parseExpression(NumBytes))
return true;
int64_t Val = 0;
@@ -2754,7 +2755,7 @@ bool AsmParser::parseDirectiveZero() {
Lex();
- getStreamer().EmitFill(NumBytes, Val);
+ getStreamer().emitFill(*NumBytes, Val, NumBytesLoc);
return false;
}
@@ -2764,17 +2765,11 @@ bool AsmParser::parseDirectiveZero() {
bool AsmParser::parseDirectiveFill() {
checkForValidSection();
- SMLoc RepeatLoc = getLexer().getLoc();
- int64_t NumValues;
- if (parseAbsoluteExpression(NumValues))
+ SMLoc NumValuesLoc = Lexer.getLoc();
+ const MCExpr *NumValues;
+ if (parseExpression(NumValues))
return true;
- if (NumValues < 0) {
- Warning(RepeatLoc,
- "'.fill' directive with negative repeat count has no effect");
- NumValues = 0;
- }
-
int64_t FillSize = 1;
int64_t FillExpr = 0;
@@ -2806,7 +2801,7 @@ bool AsmParser::parseDirectiveFill() {
if (FillSize < 0) {
Warning(SizeLoc, "'.fill' directive with negative size has no effect");
- NumValues = 0;
+ NumValues = MCConstantExpr::create(0, getStreamer().getContext());
}
if (FillSize > 8) {
Warning(SizeLoc, "'.fill' directive with size greater than 8 has been truncated to 8");
@@ -2816,15 +2811,7 @@ bool AsmParser::parseDirectiveFill() {
if (!isUInt<32>(FillExpr) && FillSize > 4)
Warning(ExprLoc, "'.fill' directive pattern has been truncated to 32-bits");
- if (NumValues > 0) {
- int64_t NonZeroFillSize = FillSize > 4 ? 4 : FillSize;
- FillExpr &= ~0ULL >> (64 - NonZeroFillSize * 8);
- for (uint64_t i = 0, e = NumValues; i != e; ++i) {
- getStreamer().EmitIntValue(FillExpr, NonZeroFillSize);
- if (NonZeroFillSize < FillSize)
- getStreamer().EmitIntValue(0, FillSize - NonZeroFillSize);
- }
- }
+ getStreamer().emitFill(*NumValues, FillSize, FillExpr, NumValuesLoc);
return false;
}
@@ -4057,8 +4044,9 @@ bool AsmParser::parseDirectiveBundleUnlo
bool AsmParser::parseDirectiveSpace(StringRef IDVal) {
checkForValidSection();
- int64_t NumBytes;
- if (parseAbsoluteExpression(NumBytes))
+ SMLoc NumBytesLoc = Lexer.getLoc();
+ const MCExpr *NumBytes;
+ if (parseExpression(NumBytes))
return true;
int64_t FillExpr = 0;
@@ -4076,12 +4064,8 @@ bool AsmParser::parseDirectiveSpace(Stri
Lex();
- if (NumBytes <= 0)
- return TokError("invalid number of bytes in '" + Twine(IDVal) +
- "' directive");
-
// FIXME: Sometimes the fill expr is 'nop' if it isn't supplied, instead of 0.
- getStreamer().EmitFill(NumBytes, FillExpr);
+ getStreamer().emitFill(*NumBytes, FillExpr, NumBytesLoc);
return false;
}
Modified: llvm/trunk/lib/MC/MCStreamer.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/MC/MCStreamer.cpp?rev=271102&r1=271101&r2=271102&view=diff
==============================================================================
--- llvm/trunk/lib/MC/MCStreamer.cpp (original)
+++ llvm/trunk/lib/MC/MCStreamer.cpp Sat May 28 00:57:48 2016
@@ -135,9 +135,18 @@ void MCStreamer::EmitGPRel32Value(const
/// EmitFill - Emit NumBytes bytes worth of the value specified by
/// FillValue. This implements directives such as '.space'.
void MCStreamer::EmitFill(uint64_t NumBytes, uint8_t FillValue) {
- const MCExpr *E = MCConstantExpr::create(FillValue, getContext());
for (uint64_t i = 0, e = NumBytes; i != e; ++i)
- EmitValue(E, 1);
+ EmitIntValue(FillValue, 1);
+}
+
+void MCStreamer::emitFill(uint64_t NumValues, int64_t Size, int64_t Expr) {
+ int64_t NonZeroSize = Size > 4 ? 4 : Size;
+ Expr &= ~0ULL >> (64 - NonZeroSize * 8);
+ for (uint64_t i = 0, e = NumValues; i != e; ++i) {
+ EmitIntValue(Expr, NonZeroSize);
+ if (NonZeroSize < Size)
+ EmitIntValue(0, Size - NonZeroSize);
+ }
}
/// The implementation in this class just redirects to EmitFill.
@@ -757,6 +766,9 @@ void MCStreamer::EmitValueImpl(const MCE
}
void MCStreamer::EmitULEB128Value(const MCExpr *Value) {}
void MCStreamer::EmitSLEB128Value(const MCExpr *Value) {}
+void MCStreamer::emitFill(const MCExpr &NumBytes, uint64_t Value, SMLoc Loc) {}
+void MCStreamer::emitFill(const MCExpr &NumValues, int64_t Size, int64_t Expr,
+ SMLoc Loc) {}
void MCStreamer::EmitValueToAlignment(unsigned ByteAlignment, int64_t Value,
unsigned ValueSize,
unsigned MaxBytesToEmit) {}
Modified: llvm/trunk/test/MC/AsmParser/directive_fill.s
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/MC/AsmParser/directive_fill.s?rev=271102&r1=271101&r2=271102&view=diff
==============================================================================
--- llvm/trunk/test/MC/AsmParser/directive_fill.s (original)
+++ llvm/trunk/test/MC/AsmParser/directive_fill.s Sat May 28 00:57:48 2016
@@ -1,66 +1,53 @@
# RUN: llvm-mc -triple i386-unknown-unknown %s 2> %t.err | FileCheck %s
# RUN: FileCheck --check-prefix=CHECK-WARNINGS %s < %t.err
+# RUN: llvm-mc -triple i386-unknown-unknown -filetype=obj -o %t.o %s 2> %t.err
+# RUN: FileCheck --check-prefix=OBJ-WARNINGS %s < %t.err
# CHECK: TEST0:
-# CHECK: .byte 10
+# CHECK: .fill 1, 1, 0xa
TEST0:
.fill 1, 1, 10
# CHECK: TEST1:
-# CHECK: .short 3
-# CHECK: .short 3
+# CHECK: .fill 2, 2, 0x3
TEST1:
.fill 2, 2, 3
# CHECK: TEST2:
-# CHECK: .long 4
-# CHECK: .long 0
+# CHECK: .fill 1, 8, 0x4
TEST2:
.fill 1, 8, 4
# CHECK: TEST3
-# CHECK: .byte 0
-# CHECK: .byte 0
-# CHECK: .byte 0
-# CHECK: .byte 0
+# CHECK: .fill 4
TEST3:
.fill 4
# CHECK: TEST4
-# CHECK: .short 0
-# CHECK: .short 0
-# CHECK: .short 0
-# CHECK: .short 0
+# CHECK: .fill 4, 2
TEST4:
.fill 4, 2
# CHECK: TEST5
-# CHECK: .short 2
-# CHECK: .byte 0
-# CHECK: .short 2
-# CHECK: .byte 0
-# CHECK: .short 2
-# CHECK: .byte 0
-# CHECK: .short 2
-# CHECK: .byte 0
+# CHECK: .fill 4, 3, 0x2
TEST5:
.fill 4, 3, 2
# CHECK: TEST6
-# CHECK: .long 2
-# CHECK: .long 0
+# CHECK: .fill 1, 8, 0x2
# CHECK-WARNINGS: '.fill' directive with size greater than 8 has been truncated to 8
TEST6:
.fill 1, 9, 2
# CHECK: TEST7
-# CHECK: .long 0
-# CHECK: .long 0
+# CHECK: .fill 1, 8, 0x0
# CHECK-WARNINGS: '.fill' directive pattern has been truncated to 32-bits
TEST7:
.fill 1, 8, 1<<32
-# CHECK-WARNINGS: '.fill' directive with negative repeat count has no effect
+# CHECK: TEST8
+# CHECK: .fill -1, 8, 0x1
+# OBJ-WARNINGS: '.fill' directive with negative repeat count has no effect
TEST8:
.fill -1, 8, 1
@@ -69,7 +56,17 @@ TEST9:
.fill 1, -1, 1
# CHECK: TEST10
-# CHECK: .short 22136
-# CHECK: .byte 52
+# CHECK: .fill 1, 3, 0x12345678
TEST10:
.fill 1, 3, 0x12345678
+
+# CHECK: TEST11
+# CHECK: .fill TEST11-TEST10, 1, 0x0
+TEST11:
+ .fill TEST11 - TEST10
+
+# CHECK: TEST12
+# CHECK: .fill TEST11-TEST12, 3, 0x12345678
+# OBJ-WARNINGS: '.fill' directive with negative repeat count has no effect
+TEST12:
+ .fill TEST11 - TEST12, 3, 0x12345678
Modified: llvm/trunk/test/MC/AsmParser/directive_space.s
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/MC/AsmParser/directive_space.s?rev=271102&r1=271101&r2=271102&view=diff
==============================================================================
--- llvm/trunk/test/MC/AsmParser/directive_space.s (original)
+++ llvm/trunk/test/MC/AsmParser/directive_space.s Sat May 28 00:57:48 2016
@@ -14,3 +14,8 @@ TEST1:
# CHECK: .space 1
TEST2:
.skip 1
+
+# CHECK: TEST3
+# CHECK: .space TEST0-TEST1
+TEST3:
+ .space TEST0 - TEST1
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