Fix botched disassembler backport

core/vip.c

@@ -320,6 +320,7 @@ static void vipWriteWorld(VB *sim, uint32_t offset, int type, int32_t value) {
     uint32_t base;  /* Base BG map index */
     uint8_t *bg;    /* Background template */
     uint32_t count; /* Number of BG maps in background */
+    int32_t  width; /* Computed affine width */
     World   *world; /* World state */
     uint32_t z;     /* Iterator */
 
@@ -381,10 +382,10 @@ static void vipWriteWorld(VB *sim, uint32_t offset, int type, int32_t value) {
         case 5: world->mp = SignExtend(value, 15); break;
         case 6: world->my = SignExtend(value, 13); break;
         case 7: /* W */
-            value = SignExtend(value, 13) + 1;
-            world->wNaffine = value < 0 ? 0 : value;
-            value = SignExtend(value, 10) + 1;
-            world->wAffine  = value < 0 ? 0 : value;
+            width = SignExtend(value, 13) + 1;
+            world->wNaffine = width < 0 ? 0 : width;
+            width = SignExtend(value, 10) + 1;
+            world->wAffine  = width < 0 ? 0 : width;
             world->width = world->bgm != 2 ? world->wNaffine : world->wAffine;
             break;
         case 8: /* H */
@@ -1005,7 +1006,7 @@ static void vipDrawAffine(VB *sim, World *world) {
     Cell    *cell;               /* Source cell */
     uint8_t *col, *row;          /* Output pixel */
     uint8_t  pixel;              /* Character pixel value */
-    uint8_t *param;              /* World parameter memory */
+    uint32_t param;              /* World parameter memory */
     int32_t  px, py;             /* Pixel source coordinates */
     int32_t  dx, dy, mp, mx, my; /* Affine parameters */
     int32_t  wx;                 /* Base world X coordinate */
@@ -1052,21 +1053,26 @@ static void vipDrawAffine(VB *sim, World *world) {
         wx = x1 - wx;
 
         /* Process all visible rows */
-        param = &sim->vip.ram[world->paramBase | (y1 - world->gy) << 4];
+        param = world->paramBase + ((y1 - world->gy) << 4);
         row   = &sim->vip.shadow[i][x1 * 224 + y1];
         for (y = y1; y < y2; y++, param += 16, row++) {
 
             /* Parse line parameters */
-            mx = (int32_t) busReadBuffer(param + 0, VB_S16) << 6;
-            mp = (int32_t) busReadBuffer(param + 2, VB_S16);
-            my = (int32_t) busReadBuffer(param + 4, VB_S16) << 6;
-            dx = (int32_t) busReadBuffer(param + 6, VB_S16);
-            dy = (int32_t) busReadBuffer(param + 8, VB_S16);
+            mx = (int32_t) busReadBuffer(&sim->vip.ram[param | 0], VB_S16) << 6;
+            mp = (int32_t) busReadBuffer(&sim->vip.ram[param | 2], VB_S16);
+            my = (int32_t) busReadBuffer(&sim->vip.ram[param | 4], VB_S16) << 6;
+            dx = (int32_t) busReadBuffer(&sim->vip.ram[param | 6], VB_S16);
+            dy = (int32_t) busReadBuffer(&sim->vip.ram[param | 8], VB_S16);
 
             /* Adjust left-edge parameters */
             if ((mp < 0) ^ i) {
-                mx += dx * (wx + mp);
-                my += dy * (wx + mp);
+                if (mp < 0) {
+                    mx += dx * (wx - mp);
+                    my += dy * (wx - mp);
+                } else {
+                    mx += dx * (wx + mp);
+                    my += dy * (wx + mp);
+                }
             } else {
                 mx += dx * wx;
                 my += dy * wx;

util/isx.c

@@ -257,7 +257,7 @@ static void* isxFrom(uint8_t *bytes, size_t length, size_t *romLength) {
         src < lowMax + 0x1000001 - highMin;
         src <<= 1
     );
-    rom = VBU_REALLOC(NULL, src);
+    rom = VBU_MEMMGR(NULL, src);
     if (rom == NULL)
         return NULL;
     *romLength = src;

util/vbu.c

@@ -5,28 +5,28 @@
 #include <string.h>
 #include <vbu.h>
 
-/* Memory management */
-#ifndef VBU_REALLOC
-    #include <stdlib.h>
-    #define VBU_REALLOC realloc
-#else
-    extern void* VBU_REALLOC(void *, size_t);
-#endif
-
 
 
 /***************************** Library Functions *****************************/
 
-/* Sign-extend an integer of variable width */
-static int32_t SignExtend(int32_t value, int32_t bits) {
-    #ifndef VB_SIGNED_PROPAGATE
-        value &= ~((uint32_t) 0xFFFFFFFF << bits);
-        bits   = (int32_t) 1 << (bits - (int32_t) 1);
-        return (value ^ bits) - bits;
-    #else
-        return value << (32 - bits) >> (32 - bits);
-    #endif
+/* Memory manager */
+#ifdef VBU_MEMMGR
+extern void* VBU_MEMMGR(void *ptr, size_t size);
+#else
+#include <stdlib.h>
+static void* VBU_MEMMGR(void *ptr, size_t size) {
+
+    /* Free a buffer */
+    if (size == 0) {
+        if (ptr != NULL)
+            free(ptr);
+        return NULL;
+    }
+
+    /* Create or resize a buffer */
+    return realloc(ptr, size);
 }
+#endif
 
 
 
@@ -46,14 +46,21 @@ VBUAPI int vbuCodeSize(VB *sim, uint32_t address) {
 }
 
 /* Initialize disassembler options with default settings */
-VBUAPI VBU_DasmConfig* vbuDasmInit(VBU_DasmConfig *config) {
+VBUAPI VBU_DasmConfig* vbuDasmDefaults(VBU_DasmConfig *config) {
+
+    /* Error checking */
+    if (config == NULL)
+        return NULL;
+
+    /* Supply default configuration */
     config->bcondNotation     = VBU_JOINED;
+    config->branchNotation    = VBU_ABSOLUTE;
     config->conditionCase     = VBU_LOWER;
     config->conditionCL       = VBU_L;
     config->conditionEZ       = VBU_Z;
     config->conditionNotation = VBU_NAMES;
     config->hexCase           = VBU_UPPER;
-    config->hexNotation       = VBU_0X;
+    config->hexNotation       = VBU_PREFIX_0X;
     config->immediateNotation = VBU_NONE;
     config->memoryNotation    = VBU_OUTSIDE;
     config->mnemonicCase      = VBU_UPPER;
@@ -69,6 +76,17 @@ VBUAPI VBU_DasmConfig* vbuDasmInit(VBU_DasmConfig *config) {
 /* Disassemble from a simulation */
 VBUAPI VBU_DasmLine* vbuDisassemble(VB *sim, uint32_t address,
     VBU_DasmConfig *config, unsigned length, int line) {
+    VBU_DasmConfig defs; /* Default settings */
+
+    /* Error checking */
+    if (sim == NULL || length == 0)
+        return NULL;
+
+    /* Supply default configuration */
+    if (config == NULL)
+        config = vbuDasmDefaults(&defs);
+
+    /* Disassemble instructions */
     return dasmDisassemble(sim, address, config, length, line);
 }
 

util/vbu.h

@@ -17,25 +17,27 @@ extern "C" {
 /********************************* Constants *********************************/
 
 /* Disassembler options */
-#define VBU_0X         0
-#define VBU_C          1
-#define VBU_DEST_FIRST 1
-#define VBU_DEST_LAST  0
-#define VBU_DOLLAR     1
-#define VBU_E          0
-#define VBU_H          2
-#define VBU_INSIDE     1
-#define VBU_JOINED     0
-#define VBU_L          0
-#define VBU_LOWER      1
-#define VBU_NAMES      1
-#define VBU_NONE       0
-#define VBU_NUMBER     1
-#define VBU_NUMBERS    0
-#define VBU_OUTSIDE    0
-#define VBU_SPLIT      1
-#define VBU_UPPER      0
-#define VBU_Z          1
+#define VBU_ABSOLUTE      0
+#define VBU_C             1
+#define VBU_DEST_FIRST    1
+#define VBU_DEST_LAST     0
+#define VBU_E             0
+#define VBU_INSIDE        1
+#define VBU_JOINED        0
+#define VBU_L             0
+#define VBU_LOWER         1
+#define VBU_NAMES         1
+#define VBU_NONE          0
+#define VBU_NUMBERS       0
+#define VBU_OUTSIDE       0
+#define VBU_PREFIX_0X     0
+#define VBU_PREFIX_DOLLAR 1
+#define VBU_PREFIX_NUMBER 1
+#define VBU_RELATIVE      1
+#define VBU_SPLIT         1
+#define VBU_SUFFIX_H      2
+#define VBU_UPPER         0
+#define VBU_Z             1
 
 
 
@@ -44,13 +46,14 @@ extern "C" {
 /* Disassembler text options */
 typedef struct {               /* Defaults listed first */
     uint8_t bcondNotation;     /* JOINED, SPLIT */
+    uint8_t branchNotation;    /* ABSOLUTE, RELATIVE */
     uint8_t conditionCase;     /* LOWER, UPPER */
     uint8_t conditionCL;       /* L, C */
     uint8_t conditionEZ;       /* Z, E */
     uint8_t conditionNotation; /* NAMES, NUMBERS */
     uint8_t hexCase;           /* UPPER, LOWER */
-    uint8_t hexNotation;       /* 0X, H, DOLLAR */
-    uint8_t immediateNotation; /* NONE, NUMBER */
+    uint8_t hexNotation;       /* PREFIX_0X, SUFFIX_H, PREFIX_DOLLAR */
+    uint8_t immediateNotation; /* NONE, SUFFIX_NUMBER */
     uint8_t memoryNotation;    /* OUTSIDE, INSIDE */
     uint8_t mnemonicCase;      /* UPPER, LOWER */
     uint8_t operandOrder;      /* DEST_LAST, DEST_FIRST */
@@ -66,7 +69,7 @@ typedef struct {
 
     /* Parsed */
     uint32_t address;    /* Memory address */
-    uint16_t code[4];    /* Instruction bytes */
+    uint8_t  code[4];    /* Instruction bytes */
     uint8_t  codeLength; /* Number of items in code */
     uint8_t  isPC;       /* Set if PC is on this line */
 
@@ -85,10 +88,10 @@ typedef struct {
 
 /******************************* API Commands ********************************/
 
-VBUAPI int             vbuCodeSize   (VB *sim, uint32_t address);
-VBUAPI VBU_DasmConfig* vbuDasmInit   (VBU_DasmConfig *config);
-VBUAPI VBU_DasmLine*   vbuDisassemble(VB *sim, uint32_t address, VBU_DasmConfig *config, unsigned length, int line);
-VBUAPI void*           vbuFromISX    (void *bytes, size_t length, size_t *romLength);
+VBUAPI int             vbuCodeSize    (VB *sim, uint32_t address);
+VBUAPI VBU_DasmConfig* vbuDasmDefaults(VBU_DasmConfig *config);
+VBUAPI VBU_DasmLine*   vbuDisassemble (VB *sim, uint32_t address, VBU_DasmConfig *config, unsigned length, int line);
+VBUAPI void*           vbuFromISX     (void *bytes, size_t length, size_t *romLength);