llvm-6502/lib/Target/NVPTX/NVPTXutil.cpp

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//===-- NVPTXutil.cpp - Functions exported to CodeGen --*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file contains the functions that can be used in CodeGen.
//
//===----------------------------------------------------------------------===//
#include "NVPTXutil.h"
#include "NVPTX.h"
using namespace llvm;
namespace llvm {
bool isParamLoad(const MachineInstr *MI)
{
if ((MI->getOpcode() != NVPTX::LD_i32_avar) &&
(MI->getOpcode() != NVPTX::LD_i64_avar))
return false;
if (MI->getOperand(2).isImm() == false)
return false;
if (MI->getOperand(2).getImm() != NVPTX::PTXLdStInstCode::PARAM)
return false;
return true;
}
#define DATA_MASK 0x7f
#define DIGIT_WIDTH 7
#define MORE_BYTES 0x80
static int encode_leb128(uint64_t val, int *nbytes,
char *space, int splen)
{
char *a;
char *end = space + splen;
a = space;
do {
unsigned char uc;
if (a >= end)
return 1;
uc = val & DATA_MASK;
val >>= DIGIT_WIDTH;
if (val != 0)
uc |= MORE_BYTES;
*a = uc;
a++;
} while (val);
*nbytes = a - space;
return 0;
}
#undef DATA_MASK
#undef DIGIT_WIDTH
#undef MORE_BYTES
uint64_t encode_leb128(const char *str)
{
union { uint64_t x; char a[8]; } temp64;
temp64.x = 0;
for (unsigned i=0,e=strlen(str); i!=e; ++i)
temp64.a[i] = str[e-1-i];
char encoded[16];
int nbytes;
int retval = encode_leb128(temp64.x, &nbytes, encoded, 16);
(void)retval;
assert(retval == 0 &&
"Encoding to leb128 failed");
assert(nbytes <= 8 &&
"Cannot support register names with leb128 encoding > 8 bytes");
temp64.x = 0;
for (int i=0; i<nbytes; ++i)
temp64.a[i] = encoded[i];
return temp64.x;
}
} // end namespace llvm