deal with some strict aliasing issues

Makefile

@@ -151,6 +151,16 @@ tools/textfilter: tools/textfilter.c
 .s.o:
 	$(CC) $(CFLAGS) -c $< -o $@
 
+# special flags - perhaps fix this someday instead?
+pico/draw.o: CFLAGS += -fno-strict-aliasing
+pico/draw2.o: CFLAGS += -fno-strict-aliasing
+pico/mode4.o: CFLAGS += -fno-strict-aliasing
+pico/cd/memory.o: CFLAGS += -fno-strict-aliasing
+pico/cd/cd_file.o: CFLAGS += -fno-strict-aliasing
+pico/cd/pcm.o: CFLAGS += -fno-strict-aliasing
+pico/cd/LC89510.o: CFLAGS += -fno-strict-aliasing
+pico/cd/gfx_cd.o: CFLAGS += -fno-strict-aliasing
+
 # random deps
 pico/carthw/svp/compiler.o : cpu/drc/emit_$(ARCH).c
 cpu/sh2/compiler.o : cpu/drc/emit_$(ARCH).c

cpu/sh2/compiler.c

@@ -1110,8 +1110,11 @@ static void emit_or_t_if_eq(int srr)
 // reg cache must be clean before call
 static int emit_memhandler_read_(int size, int ram_check)
 {
-  int arg0, arg1;
+  int arg1;
+#if 0
+  int arg0;
   host_arg2reg(arg0, 0);
+#endif
 
   rcache_clean();
 
@@ -3179,7 +3182,7 @@ void sh2_drc_flush_all(void)
 void sh2_drc_mem_setup(SH2 *sh2)
 {
   // fill the convenience pointers
-  sh2->p_bios = sh2->is_slave ? Pico32xMem->sh2_rom_s : Pico32xMem->sh2_rom_m;
+  sh2->p_bios = sh2->is_slave ? Pico32xMem->sh2_rom_s.w : Pico32xMem->sh2_rom_m.w;
   sh2->p_da = sh2->data_array;
   sh2->p_sdram = Pico32xMem->sdram;
   sh2->p_rom = Pico.rom;
@@ -3293,7 +3296,7 @@ static void *dr_get_pc_base(u32 pc, int is_slave)
 
   if ((pc & ~0x7ff) == 0) {
     // BIOS
-    ret = is_slave ? Pico32xMem->sh2_rom_s : Pico32xMem->sh2_rom_m;
+    ret = is_slave ? Pico32xMem->sh2_rom_s.w : Pico32xMem->sh2_rom_m.w;
     mask = 0x7ff;
   }
   else if ((pc & 0xfffff000) == 0xc0000000) {

pico/32x/memory.c

@@ -1208,9 +1208,9 @@ static u32 sh2_read8_cs0(u32 a, SH2 *sh2)
 
   // TODO: mirroring?
   if (!sh2->is_slave && a < sizeof(Pico32xMem->sh2_rom_m))
-    return Pico32xMem->sh2_rom_m[a ^ 1];
+    return Pico32xMem->sh2_rom_m.b[a ^ 1];
   if (sh2->is_slave  && a < sizeof(Pico32xMem->sh2_rom_s))
-    return Pico32xMem->sh2_rom_s[a ^ 1];
+    return Pico32xMem->sh2_rom_s.b[a ^ 1];
 
   if ((a & 0x3fe00) == 0x4200) {
     d = Pico32xMem->pal[(a & 0x1ff) / 2];
@@ -1263,9 +1263,9 @@ static u32 sh2_read16_cs0(u32 a, SH2 *sh2)
   }
 
   if (!sh2->is_slave && a < sizeof(Pico32xMem->sh2_rom_m))
-    return *(u16 *)(Pico32xMem->sh2_rom_m + a);
+    return Pico32xMem->sh2_rom_m.w[a / 2];
   if (sh2->is_slave  && a < sizeof(Pico32xMem->sh2_rom_s))
-    return *(u16 *)(Pico32xMem->sh2_rom_s + a);
+    return Pico32xMem->sh2_rom_s.w[a / 2];
 
   if ((a & 0x3fe00) == 0x4200) {
     d = Pico32xMem->pal[(a & 0x1ff) / 2];
@@ -1619,17 +1619,17 @@ static void get_bios(void)
   // MSH2
   if (p32x_bios_m != NULL) {
     elprintf(EL_STATUS|EL_32X, "32x: using supplied master SH2 BIOS");
-    Byteswap(Pico32xMem->sh2_rom_m, p32x_bios_m, sizeof(Pico32xMem->sh2_rom_m));
+    Byteswap(&Pico32xMem->sh2_rom_m, p32x_bios_m, sizeof(Pico32xMem->sh2_rom_m));
   }
   else {
-    pl = (u32 *)Pico32xMem->sh2_rom_m;
+    pl = (u32 *)&Pico32xMem->sh2_rom_m;
 
     // fill exception vector table to our trap address
     for (i = 0; i < 128; i++)
       pl[i] = HWSWAP(0x200);
 
     // startup code
-    memcpy(Pico32xMem->sh2_rom_m + 0x200, msh2_code, sizeof(msh2_code));
+    memcpy(&Pico32xMem->sh2_rom_m.b[0x200], msh2_code, sizeof(msh2_code));
 
     // reset SP
     pl[1] = pl[3] = HWSWAP(0x6040000);
@@ -1640,17 +1640,17 @@ static void get_bios(void)
   // SSH2
   if (p32x_bios_s != NULL) {
     elprintf(EL_STATUS|EL_32X, "32x: using supplied slave SH2 BIOS");
-    Byteswap(Pico32xMem->sh2_rom_s, p32x_bios_s, sizeof(Pico32xMem->sh2_rom_s));
+    Byteswap(&Pico32xMem->sh2_rom_s, p32x_bios_s, sizeof(Pico32xMem->sh2_rom_s));
   }
   else {
-    pl = (u32 *)Pico32xMem->sh2_rom_s;
+    pl = (u32 *)&Pico32xMem->sh2_rom_s;
 
     // fill exception vector table to our trap address
     for (i = 0; i < 128; i++)
       pl[i] = HWSWAP(0x200);
 
     // startup code
-    memcpy(Pico32xMem->sh2_rom_s + 0x200, ssh2_code, sizeof(ssh2_code));
+    memcpy(&Pico32xMem->sh2_rom_s.b[0x200], ssh2_code, sizeof(ssh2_code));
 
     // reset SP
     pl[1] = pl[3] = HWSWAP(0x603f800);

pico/cd/pico.c

@@ -43,7 +43,7 @@ PICO_INTERNAL int PicoResetMCD(void)
   memset(&Pico_mcd->pcm, 0, sizeof(Pico_mcd->pcm));
   memset(&Pico_mcd->m, 0, sizeof(Pico_mcd->m));
 
-  *(unsigned int *)(Pico_mcd->bios + 0x70) = 0xffffffff; // reset hint vector (simplest way to implement reg6)
+  memset(Pico_mcd->bios + 0x70, 0xff, 4); // reset hint vector (simplest way to implement reg6)
   Pico_mcd->m.state_flags |= 1; // s68k reset pending
   Pico_mcd->s68k_regs[3] = 1; // 2M word RAM mode with m68k access after reset
 

pico/pico_int.h

@@ -441,6 +441,7 @@ typedef struct
 		unsigned char pcm_ram[0x10000];
 		unsigned char pcm_ram_b[0x10][0x1000];
 	};
+	// FIXME: should be short
 	unsigned char s68k_regs[0x200];			// 110000: GA, not CPU regs
 	unsigned char bram[0x2000];			// 110200: 8K
 	struct mcd_misc m;				// 112200: misc
@@ -543,8 +544,14 @@ struct Pico32xMem
 #ifdef DRC_SH2
   unsigned short drcblk_da[2][1 << (12 - SH2_DRCBLK_DA_SHIFT)];
 #endif
-  unsigned char  sh2_rom_m[0x800];
+  union {
-  unsigned char  sh2_rom_s[0x400];
+    unsigned char  b[0x800];
+    unsigned short w[0x800/2];
+  } sh2_rom_m;
+  union {
+    unsigned char  b[0x400];
+    unsigned short w[0x400/2];
+  } sh2_rom_s;
   unsigned short pal[0x100];
   unsigned short pal_native[0x100];     // converted to native (for renderer)
   signed short   pwm[2*PWM_BUFF_LEN];   // PWM buffer for current frame

pico/state.c

@@ -290,7 +290,8 @@ static int state_save(void *file)
     SekPackCpu(buff, 1);
     if (Pico_mcd->s68k_regs[3] & 4) // 1M mode?
       wram_1M_to_2M(Pico_mcd->word_ram2M);
-    Pico_mcd->m.hint_vector = *(unsigned short *)(Pico_mcd->bios + 0x72);
+    memcpy(&Pico_mcd->m.hint_vector, Pico_mcd->bios + 0x72,
+      sizeof(Pico_mcd->m.hint_vector));
 
     CHECKED_WRITE_BUFF(CHUNK_S68K,     buff);
     CHECKED_WRITE_BUFF(CHUNK_PRG_RAM,  Pico_mcd->prg_ram);