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Reduced number of segment/selector checks in recompiler - minor speedup.

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This commit is contained in:
TomW 2015-07-08 20:40:37 +01:00
commit 51489d031c
4 changed files with 33 additions and 0 deletions
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22
src/codegen_ops_x86.h
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@ -462,6 +462,15 @@ static void SAR_L_IMM(int reg, int count)
static void CHECK_SEG_READ(x86seg *seg)
{
/*Segments always valid in real/V86 mode*/
if (!(cr0 & 1) || (eflags & VM_FLAG))
return;
/*CS and SS must always be valid*/
if (seg == &_cs || seg == &_ss)
return;
if (seg->checked)
return;
addbyte(0x83); /*CMP seg->base, -1*/
addbyte(0x05|0x38);
addlong((uint32_t)&seg->base);
@ -469,9 +478,20 @@ static void CHECK_SEG_READ(x86seg *seg)
addbyte(0x0f);
addbyte(0x84); /*JE end*/
addlong(BLOCK_EXIT_OFFSET - (block_pos + 4));
seg->checked = 1;
}
static void CHECK_SEG_WRITE(x86seg *seg)
{
/*Segments always valid in real/V86 mode*/
if (!(cr0 & 1) || (eflags & VM_FLAG))
return;
/*CS and SS must always be valid*/
if (seg == &_cs || seg == &_ss)
return;
if (seg->checked)
return;
addbyte(0x83); /*CMP seg->base, -1*/
addbyte(0x05|0x38);
addlong((uint32_t)&seg->base);
@ -479,6 +499,8 @@ static void CHECK_SEG_WRITE(x86seg *seg)
addbyte(0x0f);
addbyte(0x84); /*JE end*/
addlong(BLOCK_EXIT_OFFSET - (block_pos + 4));
seg->checked = 1;
}
static void CHECK_SEG_LIMITS(x86seg *seg, int end_offset)
{