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esp32: xtensa_user: Implement a few more instructions

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You can find them used in the ROM version of memcpy.
While it might be controversial if it's a good idea to use the ROM version
of these functions, it's nicer to support more instructions here anyway.
This commit is contained in:
YAMAMOTO Takashi 2021-02-24 12:52:49 +09:00 committed by Abdelatif Guettouche
parent ce6f6d4241
commit ee8cea1f4b
1 changed files with 93 additions and 0 deletions

93
arch/xtensa/src/esp32/esp32_user.c

@ -158,6 +158,36 @@ static int decode_s8i(const uint8_t *p, uint8_t *imm8, uint8_t *s,
return 0;
}
/****************************************************************************
* Name: decode_s16i
*
* Description:
* Decode S16I instruction using 32-bit aligned access.
* Return non-zero on successful decoding.
*
****************************************************************************/
static int decode_s16i(const uint8_t *p, uint8_t *imm8, uint8_t *s,
uint8_t *t)
{
/* 23 16 15 12 11 8 7 4 3 0
* | imm8 |0 1 0 1| s | t |0 0 1 0|
*/
uint8_t b0 = load_uint8(p);
uint8_t b1 = load_uint8(p + 1);
if ((b0 & 0xf) == 2 && (b1 & 0xf0) == 0x50)
{
*t = b0 >> 4;
*s = b1 & 0xf;
*imm8 = load_uint8(p + 2);
return 1;
}
return 0;
}
/****************************************************************************
* Name: decode_l8ui
*
@ -188,6 +218,36 @@ static int decode_l8ui(const uint8_t *p, uint8_t *imm8, uint8_t *s,
return 0;
}
/****************************************************************************
* Name: decode_l16ui
*
* Description:
* Decode L16UI instruction using 32-bit aligned access.
* Return non-zero on successful decoding.
*
****************************************************************************/
static int decode_l16ui(const uint8_t *p, uint8_t *imm8, uint8_t *s,
uint8_t *t)
{
/* 23 16 15 12 11 8 7 4 3 0
* | imm8 |0 0 0 1| s | t |0 0 1 0|
*/
uint8_t b0 = load_uint8(p);
uint8_t b1 = load_uint8(p + 1);
if ((b0 & 0xf) == 2 && (b1 & 0xf0) == 0x10)
{
*t = b0 >> 4;
*s = b1 & 0xf;
*imm8 = load_uint8(p + 2);
return 1;
}
return 0;
}
/****************************************************************************
* Name: advance_pc
*
@ -274,6 +334,23 @@ uint32_t *xtensa_user(int exccause, uint32_t *regs)
advance_pc(regs, 3);
return regs;
}
else if (decode_s16i(pc, &imm8, &s, &t))
{
binfo("Emulating S16I imm8=%u, s=%u (%p), t=%u (%p)\n",
(unsigned int)imm8,
(unsigned int)s,
(void *)regs[REG_A0 + s],
(unsigned int)t,
(void *)regs[REG_A0 + t]);
DEBUGASSERT(regs[REG_A0 + s] + imm8 == regs[REG_EXCVADDR]);
store_uint8(((uint8_t *)regs[REG_A0 + s]) + imm8,
regs[REG_A0 + t]);
store_uint8(((uint8_t *)regs[REG_A0 + s]) + imm8 + 1,
regs[REG_A0 + t] >> 8);
advance_pc(regs, 3);
return regs;
}
else if (decode_l8ui(pc, &imm8, &s, &t))
{
binfo("Emulating L8UI imm8=%u, s=%u (%p), t=%u (%p)\n",
@ -289,6 +366,22 @@ uint32_t *xtensa_user(int exccause, uint32_t *regs)
advance_pc(regs, 3);
return regs;
}
else if (decode_l16ui(pc, &imm8, &s, &t))
{
binfo("Emulating L16UI imm8=%u, s=%u (%p), t=%u (%p)\n",
(unsigned int)imm8,
(unsigned int)s,
(void *)regs[REG_A0 + s],
(unsigned int)t,
(void *)regs[REG_A0 + t]);
DEBUGASSERT(regs[REG_A0 + s] + imm8 == regs[REG_EXCVADDR]);
uint8_t lo = load_uint8(((uint8_t *)regs[REG_A0 + s]) + imm8);
uint8_t hi = load_uint8(((uint8_t *)regs[REG_A0 + s]) + imm8 + 1);
regs[REG_A0 + t] = (hi << 8) | lo;
advance_pc(regs, 3);
return regs;
}
}
#endif