for (i=mask|0x8000; (i&1)==0; i>>=1) low++; // Find out how high up the EA mask is\r
mask&=0xf<<low; // This is the max we can do\r
\r
- if (ea>=8) needor=1; // Need to OR to access A0-7\r
-\r
- if ((mask>>low)&8) if (ea&8) needor=0; // Ah - no we don't actually need to or, since the bit is high in r8\r
-\r
- if (forceor) needor=1; // Special case for 0x30-0x38 EAs ;)\r
+ if (ea>=8)\r
+ {\r
+ needor=1; // Need to OR to access A0-7\r
+ if ((g_op>>low)&8) { needor=0; mask|=8<<low; } // Ah - no we don't actually need to or, since the bit is high in r8\r
+ if (forceor) needor=1; // Special case for 0x30-0x38 EAs ;)\r
+ }\r
\r
ot(" and r%d,r8,#0x%.4x\n",r,mask);\r
if (needor) ot(" orr r%d,r%d,#0x%x ;@ A0-7\n",r,r,8<<low);\r
}\r
\r
// EaCalc - ARM Register 'a' = Effective Address\r
-// Trashes r0,r2 and r3\r
+// If ea>=0x10, trashes r0,r2 and r3, else nothing\r
// size values 0, 1, 2 ~ byte, word, long\r
-int EaCalc(int a,int mask,int ea,int size,int top)\r
+// mask shows usable bits in r8\r
+int EaCalc(int a,int mask,int ea,int size,int top,int sign_extend)\r
{\r
char text[32]="";\r
int func=0;\r
if (ea<0x10)\r
{\r
int noshift=0;\r
- if (size>=2||(size==0&&top)) noshift=1; // Saves one opcode\r
+ if (size>=2||(size==0&&(top||!sign_extend))) noshift=1; // Saves one opcode\r
\r
ot(";@ EaCalc : Get register index into r%d:\n",a);\r
\r
\r
if ((ea&7)==7 && step<2) step=2; // move.b (a7)+ or -(a7) steps by 2 not 1\r
\r
- EaCalcReg(2,ea,mask,0,0,1);\r
- if(mask)\r
- for (i=mask|0x8000; (i&1)==0; i>>=1) low++; // Find out how high up the EA mask is\r
- lsl=2-low; // Having a lsl #x here saves one opcode\r
- if (lsl>=0) ot(" ldr r%d,[r7,r2,lsl #%i]\n",a,lsl);\r
- else if (lsl<0) ot(" ldr r%d,[r7,r2,lsr #%i]\n",a,-lsl);\r
+ if (ea==0x1f||ea==0x27) // A7 handlers are always separate\r
+ {\r
+ ot(" ldr r%d,[r7,#0x3c] ;@ A7\n",a);\r
+ }\r
+ else\r
+ {\r
+ EaCalcReg(2,ea,mask,0,0,1);\r
+ if(mask)\r
+ for (i=mask|0x8000; (i&1)==0; i>>=1) low++; // Find out how high up the EA mask is\r
+ lsl=2-low; // Having a lsl #x here saves one opcode\r
+ if (lsl>=0) ot(" ldr r%d,[r7,r2,lsl #%i]\n",a,lsl);\r
+ else if (lsl<0) ot(" ldr r%d,[r7,r2,lsr #%i]\n",a,-lsl);\r
+ }\r
\r
if ((ea&0x38)==0x18) // (An)+\r
{\r
\r
if ((ea&0x38)==0x18||(ea&0x38)==0x20)\r
{\r
- if (lsl>=0) ot(" str r%d,[r7,r2,lsl #%i]\n",strr,lsl);\r
- else if (lsl<0) ot(" str r%d,[r7,r2,lsr #%i]\n",strr,-lsl);\r
+ if (ea==0x1f||ea==0x27)\r
+ {\r
+ ot(" str r%d,[r7,#0x3c] ;@ A7\n",strr);\r
+ }\r
+ else\r
+ {\r
+ if (lsl>=0) ot(" str r%d,[r7,r2,lsl #%i]\n",strr,lsl);\r
+ else if (lsl<0) ot(" str r%d,[r7,r2,lsr #%i]\n",strr,-lsl);\r
+ }\r
}\r
\r
if ((ea&0x38)==0x20) Cycles+=size<2 ? 6:10; // -(An) Extra cycles\r
\r
if (ea<0x30) // ($nn,An) (di)\r
{\r
- EaCalcReg(2,8,mask,0,0);\r
ot(" ldrsh r0,[r4],#2 ;@ Fetch offset\n"); pc_dirty=1;\r
+ EaCalcReg(2,8,mask,0,0);\r
ot(" ldr r2,[r7,r2,lsl #2]\n");\r
ot(" add r%d,r0,r2 ;@ Add on offset\n",a);\r
Cycles+=size<2 ? 8:12; // Extra cycles\r
}\r
\r
ot(" ldrh r2,[r4],#2 ;@ Fetch immediate value\n");\r
- ot(" ldrh r0,[r4],#2\n"); pc_dirty=1;\r
- ot(" orr r%d,r0,r2,lsl #16\n",a);\r
+ ot(" ldrh r3,[r4],#2\n"); pc_dirty=1;\r
+ ot(" orr r%d,r3,r2,lsl #16\n",a);\r
Cycles+=8; // Extra cycles\r
return 0;\r
}\r
// 'a' and 'v' can be anything but 0 is generally best (for both)\r
// If (ea<0x10) nothing is trashed, else r0-r3 is trashed\r
// If 'top' is given, the ARM register v shifted to the top, e.g. 0xc000 -> 0xc0000000\r
-// Otherwise the ARM register v is sign extended, e.g. 0xc000 -> 0xffffc000\r
+// If top is 0 and sign_extend is not, then ARM register v is sign extended,\r
+// e.g. 0xc000 -> 0xffffc000 (else it may or may not be sign extended)\r
\r
-int EaRead(int a,int v,int ea,int size,int mask,int top)\r
+int EaRead(int a,int v,int ea,int size,int mask,int top,int sign_extend)\r
{\r
char text[32]="";\r
int shift=0;\r
- \r
+ \r
shift=32-(8<<size);\r
\r
DisaPc=2; DisaGetEa(text,ea,size); // Get text version of the effective address\r
\r
if (ea<0x10)\r
{\r
- int lsl=0,low=0,i;\r
- if (size>=2||(size==0&&top)) {\r
+ int lsl=0,low=0,nsarm=size&3,i;\r
+ if (size>=2||(size==0&&(top||!sign_extend))) {\r
if(mask)\r
for (i=mask|0x8000; (i&1)==0; i>>=1) low++; // Find out how high up the EA mask is\r
lsl=2-low; // Having a lsl #2 here saves one opcode\r
}\r
\r
+ if (top||!sign_extend) nsarm=3;\r
+\r
ot(";@ EaRead : Read register[r%d] into r%d:\n",a,v);\r
\r
- if (lsl>0) ot(" ldr%s r%d,[r7,r%d,lsl #%i]\n",Narm[size&3],v,a,lsl);\r
- else if (lsl<0) ot(" ldr%s r%d,[r7,r%d,lsr #%i]\n",Narm[size&3],v,a,-lsl);\r
- else ot(" ldr%s r%d,[r7,r%d]\n",Sarm[size&3],v,a);\r
+ if (lsl>0) ot(" ldr%s r%d,[r7,r%d,lsl #%i]\n",Narm[nsarm],v,a,lsl);\r
+ else if (lsl<0) ot(" ldr%s r%d,[r7,r%d,lsr #%i]\n",Narm[nsarm],v,a,-lsl);\r
+ else ot(" ldr%s r%d,[r7,r%d]\n",Sarm[nsarm],v,a);\r
\r
- if (top && shift) ot(" mov r%d,r%d,asl #%d\n",v,v,shift);\r
+ if (top&&shift) ot(" mov r%d,r%d,asl #%d\n",v,v,shift);\r
\r
ot("\n"); return 0;\r
}\r
\r
if (top) asl=shift;\r
\r
- if (v!=a || asl) ot(" mov r%d,r%d,asl #%d\n",v,a,asl);\r
+ if (asl) ot(" mov r%d,r%d,asl #%d\n",v,a,asl);\r
+ else if (v!=a) ot(" mov r%d,r%d\n",v,a);\r
ot("\n"); return 0;\r
}\r
\r
if (ea>=0x3a && ea<=0x3b) MemHandler(2,size,a); // Fetch\r
else MemHandler(0,size,a); // Read\r
\r
- if (v!=0 || shift) {\r
- if (shift) ot(" mov r%d,r0,asl #%d\n",v,shift);\r
- else ot(" mov r%d,r0\n",v);\r
+ if (sign_extend)\r
+ {\r
+ int d_reg=0;\r
+ if (shift) {\r
+ ot(" mov r%d,r%d,asl #%d\n",v,d_reg,shift);\r
+ d_reg=v;\r
+ }\r
+ if (!top && shift) {\r
+ ot(" mov r%d,r%d,asr #%d\n",v,d_reg,shift);\r
+ d_reg=v;\r
+ }\r
+ if (d_reg != v)\r
+ ot(" mov r%d,r%d\n",v,d_reg);\r
+ }\r
+ else\r
+ {\r
+ if (top && shift)\r
+ ot(" mov r%d,r0,asl #%d\n",v,shift);\r
+ else if (v!=0)\r
+ ot(" mov r%d,r0\n",v);\r
}\r
- if (top==0 && shift) ot(" mov r%d,r%d,asr #%d\n",v,v,shift);\r
\r
ot("\n"); return 0;\r
}\r
\r
+// calculate EA and read\r
+// if (ea < 0x10) nothing is trashed\r
+// if (ea == 0x3c) r2 and r3 are trashed\r
+// else r0-r3 are trashed\r
+// size values 0, 1, 2 ~ byte, word, long\r
+// r_ea is reg to store ea in (-1 means ea is not needed), r is dst reg\r
+// if sign_extend is 0, non-32bit values will have MS bits undefined\r
+int EaCalcRead(int r_ea,int r,int ea,int size,int mask,int sign_extend)\r
+{\r
+ if (ea<0x10)\r
+ {\r
+ if (r_ea==-1)\r
+ {\r
+ r_ea=r;\r
+ if (!sign_extend) size=2;\r
+ }\r
+ }\r
+ else if (ea==0x3c) // #imm\r
+ {\r
+ r_ea=r;\r
+ }\r
+ else\r
+ {\r
+ if (r_ea==-1) r_ea=0;\r
+ }\r
+\r
+ EaCalc (r_ea,mask,ea,size,0,sign_extend);\r
+ EaRead (r_ea, r,ea,size,mask,0,sign_extend);\r
+\r
+ return 0;\r
+}\r
+\r
+int EaCalcReadNoSE(int r_ea,int r,int ea,int size,int mask)\r
+{\r
+ return EaCalcRead(r_ea,r,ea,size,mask,0);\r
+}\r
+\r
// Return 1 if we can read this ea\r
int EaCanRead(int ea,int size)\r
{\r
// Write effective address (ARM Register 'a') with ARM register 'v'\r
// Trashes r0-r3,r12,lr; 'a' can be 0 or 2+, 'v' can be 1 or higher\r
// If a==0 and v==1 it's faster though.\r
-int EaWrite(int a,int v,int ea,int size,int mask,int top)\r
+int EaWrite(int a,int v,int ea,int size,int mask,int top,int sign_extend_ea)\r
{\r
char text[32]="";\r
int shift=0;\r
if (ea<0x10)\r
{\r
int lsl=0,low=0,i;\r
- if (size>=2||(size==0&&top)) {\r
+ if (size>=2||(size==0&&(top||!sign_extend_ea))) {\r
if(mask)\r
for (i=mask|0x8000; (i&1)==0; i>>=1) low++; // Find out how high up the EA mask is\r
lsl=2-low; // Having a lsl #x here saves one opcode\r
\r
if (ea==0x3c) { ot("Error! Write EA=0x%x\n\n",ea); return 1; }\r
\r
- if (v!=1 || shift) ot(" mov r1,r%d,asr #%d\n",v,shift);\r
+ if (shift) ot(" mov r1,r%d,asr #%d\n",v,shift);\r
+ else if (v!=1) ot(" mov r1,r%d\n",v);\r
\r
MemHandler(1,size,a); // Call write handler\r
\r