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sh2 drc, fix reading from constant memory address

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This commit is contained in:
kub 2021-03-16 21:25:04 +01:00
parent d35a929551
commit 2d2387b293
2 changed files with 28 additions and 17 deletions
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3
cpu/drc/emit_x86.c
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@ -1033,8 +1033,7 @@ enum { xAX = 0, xCX, xDX, xBX, xSP, xBP, xSI, xDI, // x86-64,i386 common
#define host_instructions_updated(base, end, force) (void)(base),(void)(end) #define host_instructions_updated(base, end, force) (void)(base),(void)(end)
#define emith_update_cache() /**/ #define emith_update_cache() /**/
// NB this MUST be <0x40000000 to avoid overflow in address calculations #define emith_rw_offs_max() 0xffffffffU
#define emith_rw_offs_max() 0xfffffff // for better perfomance: <0x10000000
#ifdef __x86_64__ #ifdef __x86_64__

42
cpu/sh2/compiler.c
View file

@ -2590,8 +2590,21 @@ static void emit_le_ptr8(int cond, int r)
#endif #endif
} }
// split address by mask, in base part (upper) and offset (lower, signed!)
static uptr split_address(uptr la, uptr mask, s32 *offs)
{
uptr sign = (mask>>1) + 1; // sign bit in offset
*offs = (la & mask) | (la & sign ? ~mask : 0); // offset part, sign extended
la = (la & ~mask) + ((la & sign) << 1); // base part, corrected for offs sign
if (~mask && la == ~mask && !(*offs & sign)) { // special case la=-1 & offs>0
*offs = -*offs;
la = 0;
}
return la;
}
// NB may return either REG or TEMP // NB may return either REG or TEMP
static int emit_get_rbase_and_offs(SH2 *sh2, sh2_reg_e r, int rmode, u32 *offs) static int emit_get_rbase_and_offs(SH2 *sh2, sh2_reg_e r, int rmode, s32 *offs)
{ {
uptr omask = emith_rw_offs_max(); // offset mask uptr omask = emith_rw_offs_max(); // offset mask
u32 mask = 0; u32 mask = 0;
@ -2614,14 +2627,14 @@ static int emit_get_rbase_and_offs(SH2 *sh2, sh2_reg_e r, int rmode, u32 *offs)
a = (a + *offs) & mask; a = (a + *offs) & mask;
if (poffs == offsetof(SH2, p_da)) { if (poffs == offsetof(SH2, p_da)) {
// access sh2->data_array directly // access sh2->data_array directly
a += offsetof(SH2, data_array); a = split_address(a + offsetof(SH2, data_array), omask, offs);
emith_add_r_r_ptr_imm(hr, CONTEXT_REG, a & ~omask); emith_add_r_r_ptr_imm(hr, CONTEXT_REG, a);
} else { } else {
a = split_address(a, omask, offs);
emith_ctx_read_ptr(hr, poffs); emith_ctx_read_ptr(hr, poffs);
if (a & ~omask) if (a)
emith_add_r_r_ptr_imm(hr, hr, a & ~omask); emith_add_r_r_ptr_imm(hr, hr, a);
} }
*offs = a & omask;
return hr; return hr;
} }
@ -2637,24 +2650,23 @@ static int emit_get_rbase_and_offs(SH2 *sh2, sh2_reg_e r, int rmode, u32 *offs)
la -= (s32)((a & ~mask) - *offs); // diff between reg and memory la -= (s32)((a & ~mask) - *offs); // diff between reg and memory
hr = hr2 = rcache_get_reg(r, rmode, NULL); hr = hr2 = rcache_get_reg(r, rmode, NULL);
if ((s32)a < 0) emith_uext_ptr(hr2); if ((s32)a < 0) emith_uext_ptr(hr2);
if (la & ~omask) { la = split_address(la, omask, offs);
if (la) {
hr = rcache_get_tmp(); hr = rcache_get_tmp();
emith_add_r_r_ptr_imm(hr, hr2, la & ~omask); emith_add_r_r_ptr_imm(hr, hr2, la);
rcache_free(hr2); rcache_free(hr2);
} }
*offs = (la & omask);
} else { } else {
// known fixed host address // known fixed host address
la += (a + *offs) & mask; la = split_address(la + ((a + *offs) & mask), omask, offs);
hr = rcache_get_tmp(); hr = rcache_get_tmp();
emith_move_r_ptr_imm(hr, la & ~omask); emith_move_r_ptr_imm(hr, la);
*offs = la & omask;
} }
return hr; return hr;
} }
// read const data from const ROM address // read const data from const ROM address
static int emit_get_rom_data(SH2 *sh2, sh2_reg_e r, u32 offs, int size, u32 *val) static int emit_get_rom_data(SH2 *sh2, sh2_reg_e r, s32 offs, int size, u32 *val)
{ {
u32 a, mask; u32 a, mask;
@ -2788,7 +2800,7 @@ static void emit_memhandler_write(int size)
} }
// rd = @(Rs,#offs); rd < 0 -> return a temp // rd = @(Rs,#offs); rd < 0 -> return a temp
static int emit_memhandler_read_rr(SH2 *sh2, sh2_reg_e rd, sh2_reg_e rs, u32 offs, int size) static int emit_memhandler_read_rr(SH2 *sh2, sh2_reg_e rd, sh2_reg_e rs, s32 offs, int size)
{ {
int hr, hr2; int hr, hr2;
u32 val; u32 val;
@ -2859,7 +2871,7 @@ static int emit_memhandler_read_rr(SH2 *sh2, sh2_reg_e rd, sh2_reg_e rs, u32 off
} }
// @(Rs,#offs) = rd; rd < 0 -> write arg1 // @(Rs,#offs) = rd; rd < 0 -> write arg1
static void emit_memhandler_write_rr(SH2 *sh2, sh2_reg_e rd, sh2_reg_e rs, u32 offs, int size) static void emit_memhandler_write_rr(SH2 *sh2, sh2_reg_e rd, sh2_reg_e rs, s32 offs, int size)
{ {
int hr, hr2; int hr, hr2;
u32 val; u32 val;