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Micro-optimize PUSHW/PUSHB

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* src/sfnt.c (CHECK_STACK_AVAILABLE): New macro.
(PUSH):
(PUSH_UNCHECKED): Always define to unchecked versions,
even if TEST.
(PUSH2_UNCHECKED): New macro.
(NPUSHB):
(NPUSHW):
(PUSHB):
(PUSHW): Check the number of remaining stack elements
once.
(stack_overflow_test_args): Expect zero stack arguments.
This commit is contained in:
Po Lu 2023-08-01 14:54:30 +08:00
parent 202ddc0137
commit b022398b8f
1 changed files with 37 additions and 14 deletions
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51
src/sfnt.c
View file

@ -5708,6 +5708,17 @@ sfnt_interpret_trap (struct sfnt_interpreter *interpreter,
TRAP ("stack underflow"); \
}
#define CHECK_STACK_AVAILABLE(n) \
{ \
char *stack_end; \
\
stack_end \
= (char *) interpreter->twilight_x; \
if (((char *) (interpreter->SP + (n)) \
> stack_end)) \
TRAP ("stack overflow"); \
}
#define CHECK_PREP() \
if (!is_prep) \
TRAP ("instruction executed not valid" \
@ -5756,7 +5767,7 @@ sfnt_interpret_trap (struct sfnt_interpreter *interpreter,
? (TRAP ("stack underflow"), 0) \
: *(interpreter->SP - 1))
#ifndef TEST
#if !defined TEST || !0
#define PUSH(value) \
{ \
@ -5774,7 +5785,7 @@ sfnt_interpret_trap (struct sfnt_interpreter *interpreter,
interpreter->SP++; \
}
#else
#else /* TEST && 0 */
#define PUSH(value) \
{ \
@ -5792,12 +5803,14 @@ sfnt_interpret_trap (struct sfnt_interpreter *interpreter,
#define PUSH_UNCHECKED(value) PUSH (value)
#endif
#endif /* TEST && 0 */
#define PUSH2(high, low) \
#define PUSH2_UNCHECKED(high, low) \
{ \
PUSH ((int16_t) ((int8_t) high) << 8 \
| low); \
int16_t word; \
\
word = (((int8_t) high) << 8 | low); \
PUSH_UNCHECKED (word); \
} \
#define SRP0() \
@ -6097,6 +6110,7 @@ sfnt_interpret_trap (struct sfnt_interpreter *interpreter,
#define NPUSHB() \
{ \
int b, nbytes, IP; \
unsigned char *ip; \
\
if ((IP = interpreter->IP + 1) \
>= interpreter->num_instructions) \
@ -6109,8 +6123,10 @@ sfnt_interpret_trap (struct sfnt_interpreter *interpreter,
> interpreter->num_instructions) \
TRAP ("args to NPUSHB lie outside IS"); \
\
CHECK_STACK_AVAILABLE (nbytes); \
ip = interpreter->instructions; \
for (b = IP + 1; b < IP + 1 + nbytes; ++b) \
PUSH (interpreter->instructions[b]); \
PUSH_UNCHECKED (ip[b]); \
\
interpreter->IP += nbytes + 1; \
}
@ -6118,6 +6134,7 @@ sfnt_interpret_trap (struct sfnt_interpreter *interpreter,
#define NPUSHW() \
{ \
int b, nbytes, IP; \
unsigned char *ip; \
\
if ((IP = interpreter->IP + 1) \
>= interpreter->num_instructions) \
@ -6130,10 +6147,11 @@ sfnt_interpret_trap (struct sfnt_interpreter *interpreter,
> interpreter->num_instructions) \
TRAP ("args to NPUSHW lie outside IS"); \
\
CHECK_STACK_AVAILABLE (nbytes / 2); \
ip = interpreter->instructions; \
for (b = IP + 1; b < IP + 1 + nbytes; \
b += 2) \
PUSH2 (interpreter->instructions[b], \
interpreter->instructions[b + 1]); \
PUSH2_UNCHECKED (ip[b], ip[b + 1]); \
\
interpreter->IP += nbytes + 1; \
}
@ -6634,6 +6652,7 @@ sfnt_interpret_trap (struct sfnt_interpreter *interpreter,
#define PUSHB() \
{ \
int b, nbytes, IP; \
unsigned char *ip; \
\
IP = interpreter->IP; \
nbytes = opcode - 0xb0 + 1; \
@ -6642,8 +6661,10 @@ sfnt_interpret_trap (struct sfnt_interpreter *interpreter,
> interpreter->num_instructions) \
TRAP ("args to PUSHB lie outside IS"); \
\
CHECK_STACK_AVAILABLE (nbytes); \
ip = interpreter->instructions; \
for (b = IP + 1; b < IP + nbytes + 1; ++b) \
PUSH (interpreter->instructions[b]); \
PUSH_UNCHECKED (ip[b]); \
\
interpreter->IP += nbytes; \
}
@ -6651,6 +6672,7 @@ sfnt_interpret_trap (struct sfnt_interpreter *interpreter,
#define PUSHW() \
{ \
int b, nbytes, IP; \
unsigned char *ip; \
\
IP = interpreter->IP; \
nbytes = (opcode - 0xb8 + 1) * 2; \
@ -6659,10 +6681,11 @@ sfnt_interpret_trap (struct sfnt_interpreter *interpreter,
> interpreter->num_instructions) \
TRAP ("args to PUSHW lie outside IS"); \
\
CHECK_STACK_AVAILABLE (nbytes / 2); \
ip = interpreter->instructions; \
for (b = IP + 1; b < IP + nbytes + 1; \
b += 2) \
PUSH2 (interpreter->instructions[b], \
interpreter->instructions[b + 1]); \
PUSH2_UNCHECKED (ip[b], ip[b + 1]); \
\
interpreter->IP += nbytes; \
}
@ -16080,8 +16103,8 @@ static struct sfnt_generic_test_args pushw_test_args =
static struct sfnt_generic_test_args stack_overflow_test_args =
{
(uint32_t[100]) { },
100,
(uint32_t[]) { },
0,
true,
0,
};