llvm-project/clang/lib/Basic/TargetInfo.cpp

216 lines
6.0 KiB
C++

//===--- TargetInfo.cpp - Information about Target machine ----------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the TargetInfo and TargetInfoImpl interfaces.
//
//===----------------------------------------------------------------------===//
#include "clang/Basic/TargetInfo.h"
#include "clang/Basic/Diagnostic.h"
#include "clang/AST/Builtins.h"
#include "llvm/ADT/APFloat.h"
#include "llvm/ADT/STLExtras.h"
#include <cstdlib>
using namespace clang;
// TargetInfo Constructor.
TargetInfo::TargetInfo(const std::string &T) : Triple(T) {
// Set defaults. These should be overridden by concrete targets as needed.
CharIsSigned = true;
WCharWidth = WCharAlign = 32;
LongWidth = LongAlign = 32;
IntWidth = IntAlign = 32;
DoubleWidth = 64;
DoubleAlign = 32;
FloatFormat = &llvm::APFloat::IEEEsingle;
DoubleFormat = &llvm::APFloat::IEEEdouble;
LongDoubleFormat = &llvm::APFloat::IEEEdouble;
}
// Out of line virtual dtor for TargetInfo.
TargetInfo::~TargetInfo() {}
//===----------------------------------------------------------------------===//
static void removeGCCRegisterPrefix(const char *&Name) {
if (Name[0] == '%' || Name[0] == '#')
Name++;
}
/// isValidGCCRegisterName - Returns whether the passed in string
/// is a valid register name according to GCC. This is used by Sema for
/// inline asm statements.
bool TargetInfo::isValidGCCRegisterName(const char *Name) const {
const char * const *Names;
unsigned NumNames;
// Get rid of any register prefix.
removeGCCRegisterPrefix(Name);
if (strcmp(Name, "memory") == 0 ||
strcmp(Name, "cc") == 0)
return true;
getGCCRegNames(Names, NumNames);
// If we have a number it maps to an entry in the register name array.
if (isdigit(Name[0])) {
char *End;
int n = (int)strtol(Name, &End, 0);
if (*End == 0)
return n >= 0 && (unsigned)n < NumNames;
}
// Check register names.
for (unsigned i = 0; i < NumNames; i++) {
if (strcmp(Name, Names[i]) == 0)
return true;
}
// Now check aliases.
const GCCRegAlias *Aliases;
unsigned NumAliases;
getGCCRegAliases(Aliases, NumAliases);
for (unsigned i = 0; i < NumAliases; i++) {
for (unsigned j = 0 ; j < llvm::array_lengthof(Aliases[i].Aliases); j++) {
if (!Aliases[i].Aliases[j])
break;
if (strcmp(Aliases[i].Aliases[j], Name) == 0)
return true;
}
}
return false;
}
const char *TargetInfo::getNormalizedGCCRegisterName(const char *Name) const {
assert(isValidGCCRegisterName(Name) && "Invalid register passed in");
removeGCCRegisterPrefix(Name);
const char * const *Names;
unsigned NumNames;
getGCCRegNames(Names, NumNames);
// First, check if we have a number.
if (isdigit(Name[0])) {
char *End;
int n = (int)strtol(Name, &End, 0);
if (*End == 0) {
assert(n >= 0 && (unsigned)n < NumNames &&
"Out of bounds register number!");
return Names[n];
}
}
// Now check aliases.
const GCCRegAlias *Aliases;
unsigned NumAliases;
getGCCRegAliases(Aliases, NumAliases);
for (unsigned i = 0; i < NumAliases; i++) {
for (unsigned j = 0 ; j < llvm::array_lengthof(Aliases[i].Aliases); j++) {
if (!Aliases[i].Aliases[j])
break;
if (strcmp(Aliases[i].Aliases[j], Name) == 0)
return Aliases[i].Register;
}
}
return Name;
}
bool TargetInfo::validateOutputConstraint(const char *Name,
ConstraintInfo &info) const
{
// An output constraint must start with '=' or '+'
if (*Name != '=' && *Name != '+')
return false;
if (*Name == '+')
info = CI_ReadWrite;
else
info = CI_None;
Name++;
while (*Name) {
switch (*Name) {
default:
if (!validateAsmConstraint(*Name, info)) {
// FIXME: We temporarily return false
// so we can add more constraints as we hit it.
// Eventually, an unknown constraint should just be treated as 'g'.
return false;
}
case '&': // early clobber.
break;
case 'r': // general register.
info = (ConstraintInfo)(info|CI_AllowsRegister);
break;
case 'm': // memory operand.
info = (ConstraintInfo)(info|CI_AllowsMemory);
break;
case 'g': // general register, memory operand or immediate integer.
info = (ConstraintInfo)(info|CI_AllowsMemory|CI_AllowsRegister);
break;
}
Name++;
}
return true;
}
bool TargetInfo::validateInputConstraint(const char *Name,
unsigned NumOutputs,
ConstraintInfo &info) const {
while (*Name) {
switch (*Name) {
default:
// Check if we have a matching constraint
if (*Name >= '0' && *Name <= '9') {
unsigned i = *Name - '0';
// Check if matching constraint is out of bounds.
if (i >= NumOutputs)
return false;
} else if (!validateAsmConstraint(*Name, info)) {
// FIXME: This assert is in place temporarily
// so we can add more constraints as we hit it.
// Eventually, an unknown constraint should just be treated as 'g'.
assert(0 && "Unknown input constraint type!");
}
case '%': // commutative
// FIXME: Fail if % is used with the last operand.
break;
case 'i': // immediate integer.
case 'I':
case 'n': // immediate integer with a known value.
break;
case 'r': // general register.
info = (ConstraintInfo)(info|CI_AllowsRegister);
break;
case 'm': // memory operand.
info = (ConstraintInfo)(info|CI_AllowsMemory);
break;
case 'g': // general register, memory operand or immediate integer.
info = (ConstraintInfo)(info|CI_AllowsMemory|CI_AllowsRegister);
break;
}
Name++;
}
return true;
}