X-Git-Url: https://notaz.gp2x.de/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=cpu%2FCyclone%2FEa.cpp;h=4be33e134eabfe23aedee5f2fba4018c04d2500b;hb=8527dc450a96f7a292b7f302e8e55147628b6042;hp=39ed8a25f79a3e21c5e33770be63515a8b58e3e0;hpb=cfb3dfa0f2a36569a6b090e87568b1a1c423f75c;p=picodrive.git

diff --git a/cpu/Cyclone/Ea.cpp b/cpu/Cyclone/Ea.cpp
index 39ed8a2..4be33e1 100644
--- a/cpu/Cyclone/Ea.cpp
+++ b/cpu/Cyclone/Ea.cpp
@@ -1,6 +1,8 @@
 
 #include "app.h"
 
+int earead_check_addrerr = 1, eawrite_check_addrerr = 0;
+
 // some ops use non-standard cycle counts for EAs, so are listed here.
 // all constants borrowed from the MUSASHI core by Karl Stenerud.
 
@@ -98,11 +100,12 @@ static int EaCalcReg(int r,int ea,int mask,int forceor,int shift,int noshift=0)
   for (i=mask|0x8000; (i&1)==0; i>>=1) low++; // Find out how high up the EA mask is
   mask&=0xf<<low; // This is the max we can do
 
-  if (ea>=8) needor=1; // Need to OR to access A0-7
-
-  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
-
-  if (forceor) needor=1; // Special case for 0x30-0x38 EAs ;)
+  if (ea>=8)
+  {
+    needor=1; // Need to OR to access A0-7
+    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
+    if (forceor) needor=1; // Special case for 0x30-0x38 EAs ;)
+  }
 
   ot("  and r%d,r8,#0x%.4x\n",r,mask);
   if (needor) ot("  orr r%d,r%d,#0x%x ;@ A0-7\n",r,r,8<<low);
@@ -121,9 +124,10 @@ 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
+// If ea>=0x10, trashes r0,r2 and r3, else nothing
 // size values 0, 1, 2 ~ byte, word, long
-int EaCalc(int a,int mask,int ea,int size,int top)
+// mask shows usable bits in r8
+int EaCalc(int a,int mask,int ea,int size,int top,int sign_extend)
 {
   char text[32]="";
   int func=0;
@@ -134,7 +138,7 @@ 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);
 
@@ -147,16 +151,23 @@ int EaCalc(int a,int mask,int ea,int size,int top)
   if (ea<0x28)
   {
     int step=1<<size, strr=a;
-    int low=0,lsl,i;
+    int low=0,lsl=0,i;
 
     if ((ea&7)==7 && step<2) step=2; // move.b (a7)+ or -(a7) steps by 2 not 1
 
-    EaCalcReg(2,ea,mask,0,0,1);
-    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
-    if      (lsl>=0) ot("  ldr r%d,[r7,r2,lsl #%i]\n",a,lsl);
-    else if (lsl<0)  ot("  ldr r%d,[r7,r2,lsr #%i]\n",a,-lsl);
+    if (ea==0x1f||ea==0x27) // A7 handlers are always separate
+    {
+      ot("  ldr r%d,[r7,#0x3c] ;@ A7\n",a);
+    }
+    else
+    {
+      EaCalcReg(2,ea,mask,0,0,1);
+      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
+      if      (lsl>=0) ot("  ldr r%d,[r7,r2,lsl #%i]\n",a,lsl);
+      else if (lsl<0)  ot("  ldr r%d,[r7,r2,lsr #%i]\n",a,-lsl);
+    }
 
     if ((ea&0x38)==0x18) // (An)+
     {
@@ -169,8 +180,15 @@ int EaCalc(int a,int mask,int ea,int size,int top)
 
     if ((ea&0x38)==0x18||(ea&0x38)==0x20)
     {
-      if      (lsl>=0) ot("  str r%d,[r7,r2,lsl #%i]\n",strr,lsl);
-      else if (lsl<0)  ot("  str r%d,[r7,r2,lsr #%i]\n",strr,-lsl);
+      if (ea==0x1f||ea==0x27)
+      {
+        ot("  str r%d,[r7,#0x3c] ;@ A7\n",strr);
+      }
+      else
+      {
+        if      (lsl>=0) ot("  str r%d,[r7,r2,lsl #%i]\n",strr,lsl);
+        else if (lsl<0)  ot("  str r%d,[r7,r2,lsr #%i]\n",strr,-lsl);
+      }
     }
 
     if ((ea&0x38)==0x20) Cycles+=size<2 ? 6:10; // -(An) Extra cycles
@@ -180,8 +198,8 @@ 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
@@ -263,8 +281,8 @@ int EaCalc(int a,int mask,int ea,int size,int top)
     }
 
     ot("  ldrh r2,[r4],#2 ;@ Fetch immediate value\n");
-    ot("  ldrh r0,[r4],#2\n"); pc_dirty=1;
-    ot("  orr r%d,r0,r2,lsl #16\n",a);
+    ot("  ldrh r3,[r4],#2\n"); pc_dirty=1;
+    ot("  orr r%d,r3,r2,lsl #16\n",a);
     Cycles+=8; // Extra cycles
     return 0;
   }
@@ -277,33 +295,36 @@ 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;
-  
+ 
   shift=32-(8<<size);
 
   DisaPc=2; DisaGetEa(text,ea,size); // Get text version of the effective address
 
   if (ea<0x10)
   {
-    int lsl=0,low=0,i;
-    if (size>=2||(size==0&&top)) {
+    int lsl=0,low=0,nsarm=size&3,i;
+    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
     }
 
+    if (top||!sign_extend) nsarm=3;
+
     ot(";@ EaRead : Read register[r%d] into r%d:\n",a,v);
 
-    if      (lsl>0) ot("  ldr%s r%d,[r7,r%d,lsl #%i]\n",Narm[size&3],v,a,lsl);
-    else if (lsl<0) ot("  ldr%s r%d,[r7,r%d,lsr #%i]\n",Narm[size&3],v,a,-lsl);
-    else            ot("  ldr%s r%d,[r7,r%d]\n",Sarm[size&3],v,a);
+    if      (lsl>0) ot("  ldr%s r%d,[r7,r%d,lsl #%i]\n",Narm[nsarm],v,a,lsl);
+    else if (lsl<0) ot("  ldr%s r%d,[r7,r%d,lsr #%i]\n",Narm[nsarm],v,a,-lsl);
+    else            ot("  ldr%s r%d,[r7,r%d]\n",Sarm[nsarm],v,a);
 
-    if (top && shift) ot("  mov r%d,r%d,asl #%d\n",v,v,shift);
+    if (top&&shift) ot("  mov r%d,r%d,asl #%d\n",v,v,shift);
 
     ot("\n"); return 0;
   }
@@ -316,22 +337,79 @@ 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 (ea>=0x3a && ea<=0x3b) MemHandler(2,size,a,earead_check_addrerr); // Fetch
+  else                      MemHandler(0,size,a,earead_check_addrerr); // Read
+
+  // defaults to 1, as most things begins with a read
+  earead_check_addrerr=1;
 
-  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;
 }
 
+// calculate EA and  read
+// if (ea  < 0x10) nothing is trashed
+// if (ea == 0x3c) r2 and r3 are trashed
+// else r0-r3 are trashed
+// size values 0, 1, 2 ~ byte, word, long
+// r_ea is reg to store ea in (-1 means ea is not needed), r is dst reg
+// if sign_extend is 0, non-32bit values will have MS bits undefined
+int EaCalcRead(int r_ea,int r,int ea,int size,int mask,int sign_extend)
+{
+  if (ea<0x10)
+  {
+    if (r_ea==-1)
+    {
+      r_ea=r;
+      if (!sign_extend) size=2;
+    }
+  }
+  else if (ea==0x3c) // #imm
+  {
+    r_ea=r;
+  }
+  else
+  {
+    if (r_ea==-1) r_ea=0;
+  }
+
+  EaCalc (r_ea,mask,ea,size,0,sign_extend);
+  EaRead (r_ea,   r,ea,size,mask,0,sign_extend);
+
+  return 0;
+}
+
+int EaCalcReadNoSE(int r_ea,int r,int ea,int size,int mask)
+{
+  return EaCalcRead(r_ea,r,ea,size,mask,0);
+}
+
 // Return 1 if we can read this ea
 int EaCanRead(int ea,int size)
 {
@@ -352,7 +430,7 @@ 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 +444,7 @@ 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
@@ -386,9 +464,14 @@ 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,eawrite_check_addrerr); // Call write handler
 
-  MemHandler(1,size,a); // Call write handler
+  // not check by default, because most cases are rmw and
+  // address was already checked before reading
+  eawrite_check_addrerr = 0;
 
   ot("\n"); return 0;
 }