Temporarily revert r61019, r61030, and r61040. These were breaking LLVM Release

builds.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61094 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Bill Wendling 2008-12-16 19:06:48 +00:00
parent 905ff1ebc4
commit 6fa311c233
10 changed files with 41 additions and 111 deletions

View File

@ -192,11 +192,11 @@ and returns MustAlias, MayAlias, or NoAlias as appropriate.
<div class="doc_text">
<p>The NoAlias response is used when the two pointers refer to distinct objects,
regardless of whether the pointers compare equal. For example, freed pointers
don't alias any pointers that were allocated afterwards. As a degenerate case,
pointers returned by malloc(0) have no bytes for an object, and are considered
NoAlias even when malloc returns the same pointer. The same rule applies to
NULL pointers.</p>
even regardless of whether the pointers compare equal. For example, freed
pointers don't alias any pointers that were allocated afterwards. As a
degenerate case, pointers returned by malloc(0) have no bytes for an object,
and are considered NoAlias even when malloc returns the same pointer. The same
rule applies to NULL pointers.</p>
<p>The MayAlias response is used whenever the two pointers might refer to the
same object. If the two memory objects overlap, but do not start at the same

View File

@ -894,15 +894,9 @@ declare signext i8 @returns_signed_char()
parameter. The caller is responsible for ensuring that this is the
case. On a function return value, <tt>noalias</tt> additionally indicates
that the pointer does not alias any other pointers visible to the
caller. For further details, please see the discussion of the NoAlias
response in
<a href="http://llvm.org/docs/AliasAnalysis.html#MustMayNo">alias
analysis</a>.</dd>
<dt><tt>nocapture</tt></dt>
<dd>This indicates that the callee does not make any copies of the pointer
that outlive the callee itself. This is not a valid attribute for return
values.</dd>
caller. Note that this applies only to pointers that can be used to actually
load/store a value: NULL, unique pointers from malloc(0), and freed pointers
are considered to not alias anything.</dd>
<dt><tt>nest</tt></dt>
<dd>This indicates that the pointer parameter can be excised using the

View File

@ -15,7 +15,6 @@
#ifndef LLVM_ATTRIBUTES_H
#define LLVM_ATTRIBUTES_H
#include "llvm/Support/MathExtras.h"
#include <cassert>
#include <string>
@ -24,7 +23,7 @@ class Type;
/// Attributes - A bitset of attributes.
typedef unsigned Attributes;
namespace Attribute {
/// Function parameters and results can have attributes to indicate how they
@ -45,18 +44,16 @@ const Attributes ByVal = 1<<7; ///< Pass structure by value
const Attributes Nest = 1<<8; ///< Nested function static chain
const Attributes ReadNone = 1<<9; ///< Function does not access memory
const Attributes ReadOnly = 1<<10; ///< Function only reads from memory
const Attributes NoInline = 1<<11; ///< inline=never
const Attributes AlwaysInline = 1<<12; ///< inline=always
const Attributes OptimizeForSize = 1<<13; ///< opt_size
const Attributes StackProtect = 1<<14; ///< Stack protection.
const Attributes StackProtectReq = 1<<15; ///< Stack protection required.
const Attributes Alignment = 31<<16; ///< Alignment of parameter (5 bits)
// stored as log2 of alignment with +1 bias
// 0 means unaligned different from align 1
const Attributes NoCapture = 1<<21; ///< Function creates no aliases of pointer
const Attributes NoInline = 1<<11; // inline=never
const Attributes AlwaysInline = 1<<12; // inline=always
const Attributes OptimizeForSize = 1<<13; // opt_size
const Attributes StackProtect = 1<<14; // Stack protection.
const Attributes StackProtectReq = 1<<15; // Stack protection required.
const Attributes Alignment = 0xffff<<16; ///< Alignment of parameter (16 bits)
// 0 = unknown, else in clear (not log)
/// @brief Attributes that only apply to function parameters.
const Attributes ParameterOnly = ByVal | Nest | StructRet | NoCapture;
const Attributes ParameterOnly = ByVal | Nest | StructRet;
/// @brief Attributes that only apply to function.
const Attributes FunctionOnly = NoReturn | NoUnwind | ReadNone | ReadOnly |
@ -67,7 +64,7 @@ const Attributes VarArgsIncompatible = StructRet;
/// @brief Attributes that are mutually incompatible.
const Attributes MutuallyIncompatible[4] = {
ByVal | InReg | Nest | StructRet,
ByVal | InReg | Nest | StructRet,
ZExt | SExt,
ReadNone | ReadOnly,
NoInline | AlwaysInline
@ -79,9 +76,7 @@ Attributes typeIncompatible(const Type *Ty);
/// This turns an int alignment (a power of 2, normally) into the
/// form used internally in Attributes.
inline Attributes constructAlignmentFromInt(unsigned i) {
assert(isPowerOf2_32(i) && "Alignment must be a power of two.");
assert(i <= 0x40000000 && "Alignment too large.");
return (Log2_32(i)+1) << 16;
return (i << 16);
}
/// The set of Attributes set in Attributes is converted to a
@ -180,7 +175,7 @@ public:
/// getParamAlignment - Return the alignment for the specified function
/// parameter.
unsigned getParamAlignment(unsigned Idx) const {
return 1ull << (((getAttributes(Idx) & Attribute::Alignment) >> 16) - 1);
return (getAttributes(Idx) & Attribute::Alignment) >> 16;
}
/// hasAttrSomewhere - Return true if the specified attribute is set for at

View File

@ -63,23 +63,12 @@ static bool AddressMightEscape(const Value *V) {
// callees could modify it.
break; // next use
case Instruction::Call:
// If the argument to the call has the nocapture attribute, then the call
// may store or load to the pointer, but it cannot escape.
if (cast<CallInst>(I)->paramHasAttr(UI.getOperandNo(),
Attribute::NoCapture))
continue;
// FIXME: MemIntrinsics should have their operands marked nocapture!
if (isa<MemIntrinsic>(I))
continue; // next use
return true;
case Instruction::Invoke:
// If the argument to the call has the nocapture attribute, then the call
// may store or load to the pointer, but it cannot escape.
if (cast<InvokeInst>(I)->paramHasAttr(UI.getOperandNo()-2,
Attribute::NoCapture))
continue;
return true;
// If the call is to a few known safe intrinsics, we know that it does
// not escape.
// TODO: Eventually just check the 'nocapture' attribute.
if (!isa<MemIntrinsic>(I))
return true;
break; // next use
default:
return true;
}

View File

@ -491,7 +491,6 @@ int LLLexer::LexIdentifier() {
KEYWORD("nounwind", NOUNWIND);
KEYWORD("noreturn", NORETURN);
KEYWORD("noalias", NOALIAS);
KEYWORD("nocapture", NOCAPTURE);
KEYWORD("byval", BYVAL);
KEYWORD("nest", NEST);
KEYWORD("readnone", READNONE);

View File

@ -1136,8 +1136,8 @@ Module *llvm::RunVMAsmParser(llvm::MemoryBuffer *MB) {
%token <OtherOpVal> EXTRACTVALUE INSERTVALUE
// Function Attributes
%token SIGNEXT ZEROEXT NORETURN INREG SRET NOUNWIND NOALIAS NOCAPTURE BYVAL
%token READNONE READONLY GC OPTSIZE NOINLINE ALWAYSINLINE SSP SSPREQ NEST
%token SIGNEXT ZEROEXT NORETURN INREG SRET NOUNWIND NOALIAS BYVAL NEST
%token READNONE READONLY GC OPTSIZE NOINLINE ALWAYSINLINE SSP SSPREQ
// Visibility Styles
%token DEFAULT HIDDEN PROTECTED
@ -1265,16 +1265,15 @@ OptCallingConv : /*empty*/ { $$ = CallingConv::C; } |
CHECK_FOR_ERROR
};
Attribute : ZEROEXT { $$ = Attribute::ZExt; }
| ZEXT { $$ = Attribute::ZExt; }
| SIGNEXT { $$ = Attribute::SExt; }
| SEXT { $$ = Attribute::SExt; }
| INREG { $$ = Attribute::InReg; }
| SRET { $$ = Attribute::StructRet; }
| NOALIAS { $$ = Attribute::NoAlias; }
| NOCAPTURE { $$ = Attribute::NoCapture; }
| BYVAL { $$ = Attribute::ByVal; }
| NEST { $$ = Attribute::Nest; }
Attribute : ZEROEXT { $$ = Attribute::ZExt; }
| ZEXT { $$ = Attribute::ZExt; }
| SIGNEXT { $$ = Attribute::SExt; }
| SEXT { $$ = Attribute::SExt; }
| INREG { $$ = Attribute::InReg; }
| SRET { $$ = Attribute::StructRet; }
| NOALIAS { $$ = Attribute::NoAlias; }
| BYVAL { $$ = Attribute::ByVal; }
| NEST { $$ = Attribute::Nest; }
| ALIGN EUINT64VAL { $$ =
Attribute::constructAlignmentFromInt($2); }
;
@ -1332,8 +1331,6 @@ OptAlign : /*empty*/ { $$ = 0; } |
$$ = $2;
if ($$ != 0 && !isPowerOf2_32($$))
GEN_ERROR("Alignment must be a power of two");
if ($$ > 0x40000000)
GEN_ERROR("Alignment too large");
CHECK_FOR_ERROR
};
OptCAlign : /*empty*/ { $$ = 0; } |
@ -1341,8 +1338,6 @@ OptCAlign : /*empty*/ { $$ = 0; } |
$$ = $3;
if ($$ != 0 && !isPowerOf2_32($$))
GEN_ERROR("Alignment must be a power of two");
if ($$ > 0x40000000)
GEN_ERROR("Alignment too large");
CHECK_FOR_ERROR
};
@ -1372,8 +1367,6 @@ GlobalVarAttribute : SectionString {
| ALIGN EUINT64VAL {
if ($2 != 0 && !isPowerOf2_32($2))
GEN_ERROR("Alignment must be a power of two");
if ($2 > 0x40000000)
GEN_ERROR("Alignment too large");
CurGV->setAlignment($2);
CHECK_FOR_ERROR
};

View File

@ -362,20 +362,6 @@ bool BitcodeReader::ParseAttributeBlock() {
Attributes RetAttribute = Attribute::None;
Attributes FnAttribute = Attribute::None;
for (unsigned i = 0, e = Record.size(); i != e; i += 2) {
// FIXME: remove in LLVM 3.0
// The alignment is stored as a 16-bit raw value from bits 31--16.
// We shift the bits above 31 down by 11 bits.
unsigned Alignment = (Record[i+1] & (0xffffull << 16)) >> 16;
if (Alignment && !isPowerOf2_32(Alignment))
return Error("Alignment is not a power of two.");
Attributes ReconstitutedAttr = Record[i+1] & 0xffff;
if (Alignment)
ReconstitutedAttr |= Attribute::constructAlignmentFromInt(Alignment);
ReconstitutedAttr |= (Record[i+1] & (0xffffull << 32)) >> 11;
Record[i+1] = ReconstitutedAttr;
if (Record[i] == 0)
RetAttribute = Record[i+1];
else if (Record[i] == ~0U)

View File

@ -122,17 +122,7 @@ static void WriteAttributeTable(const ValueEnumerator &VE,
for (unsigned i = 0, e = A.getNumSlots(); i != e; ++i) {
const AttributeWithIndex &PAWI = A.getSlot(i);
Record.push_back(PAWI.Index);
// FIXME: remove in LLVM 3.0
// Store the alignment in the bitcode as a 16-bit raw value instead of a
// 5-bit log2 encoded value. Shift the bits above the alignment up by
// 11 bits.
uint64_t FauxAttr = PAWI.Attrs & 0xffff;
if (PAWI.Attrs & Attribute::Alignment)
FauxAttr |= (1ull<<16)<<(((PAWI.Attrs & Attribute::Alignment)-1) >> 16);
FauxAttr |= (PAWI.Attrs & (0x3FFull << 21)) << 11;
Record.push_back(FauxAttr);
Record.push_back(PAWI.Attrs);
}
Stream.EmitRecord(bitc::PARAMATTR_CODE_ENTRY, Record);

View File

@ -37,8 +37,6 @@ std::string Attribute::getAsString(Attributes Attrs) {
Result += "inreg ";
if (Attrs & Attribute::NoAlias)
Result += "noalias ";
if (Attrs & Attribute::NoCapture)
Result += "nocapture ";
if (Attrs & Attribute::StructRet)
Result += "sret ";
if (Attrs & Attribute::ByVal)
@ -61,11 +59,10 @@ std::string Attribute::getAsString(Attributes Attrs) {
Result += "sspreq ";
if (Attrs & Attribute::Alignment) {
Result += "align ";
Result += utostr(1ull << (((Attrs & Attribute::Alignment)>>16) - 1));
Result += utostr((Attrs & Attribute::Alignment) >> 16);
Result += " ";
}
// Trim the trailing space.
assert(!Result.empty() && "Unknown attribute!");
Result.erase(Result.end()-1);
return Result;
}
@ -79,7 +76,7 @@ Attributes Attribute::typeIncompatible(const Type *Ty) {
if (!isa<PointerType>(Ty))
// Attributes that only apply to pointers.
Incompatible |= ByVal | Nest | NoAlias | StructRet | NoCapture;
Incompatible |= ByVal | Nest | NoAlias | StructRet;
return Incompatible;
}

View File

@ -1,13 +0,0 @@
; RUN: llvm-as < %s | opt -basicaa -gvn -instcombine | llvm-dis | grep {ret i32 0}
declare i32* @test(i32* nocapture)
define i32 @test2() {
%P = alloca i32
%Q = call i32* @test(i32* %P)
%a = load i32* %P
store i32 4, i32* %Q ;; cannot clobber P since it is nocapture.
%b = load i32* %P
%c = sub i32 %a, %b
ret i32 %c
}