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some optimizations

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git-svn-id: file:///home/notaz/opt/svn/PicoDrive@178 be3aeb3a-fb24-0410-a615-afba39da0efa
This commit is contained in:
notaz 2007-06-30 22:24:39 +00:00
parent cfb3dfa0f2
commit b637c56aad
17 changed files with 160 additions and 102 deletions
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47
cpu/Cyclone/Ea.cpp
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@ -123,7 +123,7 @@ static int EaCalcReg(int r,int ea,int mask,int forceor,int shift,int noshift=0)
// EaCalc - ARM Register 'a' = Effective Address
// Trashes r0,r2 and r3
// size values 0, 1, 2 ~ byte, word, long
int EaCalc(int a,int mask,int ea,int size,int top)
int EaCalc(int a,int mask,int ea,int size,int top,int sign_extend)
{
char text[32]="";
int func=0;
@ -134,7 +134,7 @@ int EaCalc(int a,int mask,int ea,int size,int top)
if (ea<0x10)
{
int noshift=0;
if (size>=2||(size==0&&top)) noshift=1; // Saves one opcode
if (size>=2||(size==0&&(top||!sign_extend))) noshift=1; // Saves one opcode
ot(";@ EaCalc : Get register index into r%d:\n",a);
@ -180,8 +180,8 @@ int EaCalc(int a,int mask,int ea,int size,int top)
if (ea<0x30) // ($nn,An) (di)
{
EaCalcReg(2,8,mask,0,0);
ot(" ldrsh r0,[r4],#2 ;@ Fetch offset\n"); pc_dirty=1;
EaCalcReg(2,8,mask,0,0);
ot(" ldr r2,[r7,r2,lsl #2]\n");
ot(" add r%d,r0,r2 ;@ Add on offset\n",a);
Cycles+=size<2 ? 8:12; // Extra cycles
@ -277,9 +277,10 @@ int EaCalc(int a,int mask,int ea,int size,int top)
// 'a' and 'v' can be anything but 0 is generally best (for both)
// If (ea<0x10) nothing is trashed, else r0-r3 is trashed
// If 'top' is given, the ARM register v shifted to the top, e.g. 0xc000 -> 0xc0000000
// Otherwise the ARM register v is sign extended, e.g. 0xc000 -> 0xffffc000
// If top is 0 and sign_extend is not, then ARM register v is sign extended,
// e.g. 0xc000 -> 0xffffc000 (else it may or may not be sign extended)
int EaRead(int a,int v,int ea,int size,int mask,int top)
int EaRead(int a,int v,int ea,int size,int mask,int top,int sign_extend)
{
char text[32]="";
int shift=0;
@ -291,7 +292,7 @@ int EaRead(int a,int v,int ea,int size,int mask,int top)
if (ea<0x10)
{
int lsl=0,low=0,i;
if (size>=2||(size==0&&top)) {
if (size>=2||(size==0&&(top||!sign_extend))) {
if(mask)
for (i=mask|0x8000; (i&1)==0; i>>=1) low++; // Find out how high up the EA mask is
lsl=2-low; // Having a lsl #2 here saves one opcode
@ -316,18 +317,35 @@ int EaRead(int a,int v,int ea,int size,int mask,int top)
if (top) asl=shift;
if (v!=a || asl) ot(" mov r%d,r%d,asl #%d\n",v,a,asl);
if (asl) ot(" mov r%d,r%d,asl #%d\n",v,a,asl);
else if (v!=a) ot(" mov r%d,r%d\n",v,a);
ot("\n"); return 0;
}
if (ea>=0x3a && ea<=0x3b) MemHandler(2,size,a); // Fetch
else MemHandler(0,size,a); // Read
if (v!=0 || shift) {
if (shift) ot(" mov r%d,r0,asl #%d\n",v,shift);
else ot(" mov r%d,r0\n",v);
if (sign_extend)
{
int d_reg=0;
if (shift) {
ot(" mov r%d,r%d,asl #%d\n",v,d_reg,shift);
d_reg=v;
}
if (!top && shift) {
ot(" mov r%d,r%d,asr #%d\n",v,d_reg,shift);
d_reg=v;
}
if (d_reg != v)
ot(" mov r%d,r%d\n",v,d_reg);
}
else
{
if (top && shift)
ot(" mov r%d,r0,asl #%d\n",v,shift);
else if (v!=0)
ot(" mov r%d,r0\n",v);
}
if (top==0 && shift) ot(" mov r%d,r%d,asr #%d\n",v,v,shift);
ot("\n"); return 0;
}
@ -352,7 +370,7 @@ int EaCanRead(int ea,int size)
// Write effective address (ARM Register 'a') with ARM register 'v'
// Trashes r0-r3,r12,lr; 'a' can be 0 or 2+, 'v' can be 1 or higher
// If a==0 and v==1 it's faster though.
int EaWrite(int a,int v,int ea,int size,int mask,int top)
int EaWrite(int a,int v,int ea,int size,int mask,int top,int sign_extend_ea)
{
char text[32]="";
int shift=0;
@ -366,7 +384,7 @@ int EaWrite(int a,int v,int ea,int size,int mask,int top)
if (ea<0x10)
{
int lsl=0,low=0,i;
if (size>=2||(size==0&&top)) {
if (size>=2||(size==0&&(top||!sign_extend_ea))) {
if(mask)
for (i=mask|0x8000; (i&1)==0; i>>=1) low++; // Find out how high up the EA mask is
lsl=2-low; // Having a lsl #x here saves one opcode
@ -386,7 +404,8 @@ int EaWrite(int a,int v,int ea,int size,int mask,int top)
if (ea==0x3c) { ot("Error! Write EA=0x%x\n\n",ea); return 1; }
if (v!=1 || shift) ot(" mov r1,r%d,asr #%d\n",v,shift);
if (shift) ot(" mov r1,r%d,asr #%d\n",v,shift);
else if (v!=1) ot(" mov r1,r%d\n",v);
MemHandler(1,size,a); // Call write handler