fix up stack pointer adjustments

llvm-svn: 20442
This commit is contained in:
Andrew Lenharth 2005-03-04 21:40:02 +00:00
parent c01e2f76c3
commit f3cd1477c3
1 changed files with 22 additions and 18 deletions

View File

@ -30,22 +30,25 @@
#include <iostream>
using namespace llvm;
static long getLower16(long l)
{
long y = l / 65536;
if (l % 65536 > 32767)
++y;
return l - y * 65536;
}
//These describe LDAx
static const long IMM_LOW = 0xffffffffffff8000;
static const long IMM_HIGH = 0x0000000000007fff;
static const long IMM_MULT = 65536;
static long getUpper16(long l)
{
long y = l / 65536;
if (l % 65536 > 32767)
long y = l / IMM_MULT;
if (l % IMM_MULT > IMM_HIGH)
++y;
return y;
}
static long getLower16(long l)
{
long h = getUpper16(l);
return l - h * IMM_MULT;
}
AlphaRegisterInfo::AlphaRegisterInfo()
: AlphaGenRegisterInfo(Alpha::ADJUSTSTACKDOWN, Alpha::ADJUSTSTACKUP)
{
@ -183,7 +186,7 @@ AlphaRegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator II) const {
DEBUG(std::cerr << "Corrected Offset " << Offset <<
" for stack size: " << MF.getFrameInfo()->getStackSize() << "\n");
if (Offset > 32767 || Offset < -32768) {
if (Offset > IMM_HIGH || Offset < IMM_LOW) {
//so in this case, we need to use a temporary register, and move the original
//inst off the SP/FP
//fix up the old:
@ -212,7 +215,7 @@ void AlphaRegisterInfo::emitPrologue(MachineFunction &MF) const {
MBB.insert(MBBI, MI);
// Get the number of bytes to allocate from the FrameInfo
unsigned NumBytes = MFI->getStackSize();
long NumBytes = MFI->getStackSize();
if (MFI->hasCalls() && !FP) {
// We reserve argument space for call sites in the function immediately on
@ -234,13 +237,14 @@ void AlphaRegisterInfo::emitPrologue(MachineFunction &MF) const {
MFI->setStackSize(NumBytes);
// adjust stack pointer: r30 -= numbytes
if (NumBytes <= 32767) {
MI=BuildMI(Alpha::LDA, 2, Alpha::R30).addImm(-NumBytes).addReg(Alpha::R30);
NumBytes = -NumBytes;
if (NumBytes >= IMM_LOW) {
MI=BuildMI(Alpha::LDA, 2, Alpha::R30).addImm(NumBytes).addReg(Alpha::R30);
MBB.insert(MBBI, MI);
} else if ((unsigned long)NumBytes <= (unsigned long)32767 * (unsigned long)65536) {
MI=BuildMI(Alpha::LDAH, 2, Alpha::R30).addImm(getUpper16(-NumBytes)).addReg(Alpha::R30);
} else if (getUpper16(NumBytes) >= IMM_LOW) {
MI=BuildMI(Alpha::LDAH, 2, Alpha::R30).addImm(getUpper16(NumBytes)).addReg(Alpha::R30);
MBB.insert(MBBI, MI);
MI=BuildMI(Alpha::LDA, 2, Alpha::R30).addImm(getLower16(-NumBytes)).addReg(Alpha::R30);
MI=BuildMI(Alpha::LDA, 2, Alpha::R30).addImm(getLower16(NumBytes)).addReg(Alpha::R30);
MBB.insert(MBBI, MI);
} else {
std::cerr << "Too big a stack frame at " << NumBytes << "\n";
@ -285,10 +289,10 @@ void AlphaRegisterInfo::emitEpilogue(MachineFunction &MF,
if (NumBytes != 0)
{
if (NumBytes <= 32767) {
if (NumBytes <= IMM_HIGH) {
MI=BuildMI(Alpha::LDA, 2, Alpha::R30).addImm(NumBytes).addReg(Alpha::R30);
MBB.insert(MBBI, MI);
} else if ((unsigned long)NumBytes <= (unsigned long)32767 * (unsigned long)65536) {
} else if (getUpper16(NumBytes) <= IMM_HIGH) {
MI=BuildMI(Alpha::LDAH, 2, Alpha::R30).addImm(getUpper16(NumBytes)).addReg(Alpha::R30);
MBB.insert(MBBI, MI);
MI=BuildMI(Alpha::LDA, 2, Alpha::R30).addImm(getLower16(NumBytes)).addReg(Alpha::R30);