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PREFETCH suffered from the same problem as BACKTRACK (which is really WebStorm's problem, but whatever)

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This commit is contained in:
Jeff Parsons 2015-11-02 12:26:58 -08:00
commit 5db38752aa
1 changed files with 13 additions and 13 deletions
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26
modules/pcjs/lib/x86cpu.js
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@ -206,16 +206,16 @@ Component.subclass(X86CPU, CPU);
if (PREFETCH) {
/*
* NOTE: X86CPU.PREFETCH.LENGTH must be set to a power of two, so that LENGTH - 1 will form a mask
* NOTE: X86CPU.PFINFO.LENGTH must be set to a power of two, so that LENGTH - 1 will form a mask
* (IP_MASK) we can use to create a sliding prefetch window of LENGTH bytes. We also zero the low
* 2 bits of IP_MASK so that the sliding window always starts on a 32-bit (long) boundary. Finally,
* instead breaking breaking all the longs we prefetch into bytes, we simply store the longs as-is
* into every 4th element of the queue (the queue is sparse array).
*/
X86CPU.PREFETCH = {
X86CPU.PFINFO = {
LENGTH: 16 // 16 generates a 16-byte prefetch queue consisting of 4 32-bit entries
};
X86CPU.PREFETCH.IP_MASK = ((X86CPU.PREFETCH.LENGTH - 1) & ~0x3);
X86CPU.PFINFO.IP_MASK = ((X86CPU.PFINFO.LENGTH - 1) & ~0x3);
}
/**
@ -235,7 +235,7 @@ if (PREFETCH) {
* 8: [dword]
* 12: [dword]
*
* The actual regLIP mask is X86CPU.PREFETCH.IP_MASK; ie, (X86CPU.PREFETCH.LENGTH - 1) & ~0x3.
* The actual regLIP mask is X86CPU.PFINFO.IP_MASK; ie, (X86CPU.PFINFO.LENGTH - 1) & ~0x3.
*
* On refilling, the queue is always filled to capacity, and cbPrefetch is set to its maximum
* value (eg, a value from 16 to 13, depending on whether "regLIP & 0x3" is 0, 1, 2 or 3).
@ -266,7 +266,7 @@ X86CPU.prototype.initMemory = function(aMemBlocks, nBlockShift)
this.nBlockMask = this.nBlockTotal - 1;
if (PREFETCH) {
// this.nBusCycles = 0;
this.adwPrefetch = new Array(X86CPU.PREFETCH.LENGTH);
this.adwPrefetch = new Array(X86CPU.PFINFO.LENGTH);
}
};
@ -2179,7 +2179,7 @@ X86CPU.prototype.resetIP = function(dec)
* That's the bad news; the good news is that this extra refill should only hurt performance of the
* first repetition.
*/
if (this.cbPrefetch > X86CPU.PREFETCH.LENGTH) this.refillPrefetch();
if (this.cbPrefetch > X86CPU.PFINFO.LENGTH) this.refillPrefetch();
} else {
this.regLIP = this.opLIP;
}
@ -3419,7 +3419,7 @@ X86CPU.prototype.getBytePrefetch = function()
this.refillPrefetch();
if (!this.cbPrefetch) return this.getByte(this.regLIP);
}
var b = (this.adwPrefetch[this.regLIP & X86CPU.PREFETCH.IP_MASK] >> ((this.regLIP & 0x3) << 3)) & 0xff;
var b = (this.adwPrefetch[this.regLIP & X86CPU.PFINFO.IP_MASK] >> ((this.regLIP & 0x3) << 3)) & 0xff;
this.assert(b === this.getByte(this.regLIP));
this.cbPrefetch--;
return b;
@ -3441,8 +3441,8 @@ X86CPU.prototype.getShortPrefetch = function()
}
}
var shift = (this.regLIP & 0x3) << 3;
var w = (this.adwPrefetch[this.regLIP & X86CPU.PREFETCH.IP_MASK] >>> shift) & 0xffff;
if (shift > 16) w |= (this.adwPrefetch[(this.regLIP + 4) & X86CPU.PREFETCH.IP_MASK] & 0xff) << 8;
var w = (this.adwPrefetch[this.regLIP & X86CPU.PFINFO.IP_MASK] >>> shift) & 0xffff;
if (shift > 16) w |= (this.adwPrefetch[(this.regLIP + 4) & X86CPU.PFINFO.IP_MASK] & 0xff) << 8;
this.assert(w === this.getShort(this.regLIP));
this.cbPrefetch -= 2;
return w;
@ -3464,8 +3464,8 @@ X86CPU.prototype.getLongPrefetch = function()
}
}
var shift = (this.regLIP & 0x3) << 3;
var l = (this.adwPrefetch[this.regLIP & X86CPU.PREFETCH.IP_MASK] >>> shift)|0;
if (shift) l |= this.adwPrefetch[(this.regLIP + 4) & X86CPU.PREFETCH.IP_MASK] << (32 - shift);
var l = (this.adwPrefetch[this.regLIP & X86CPU.PFINFO.IP_MASK] >>> shift)|0;
if (shift) l |= this.adwPrefetch[(this.regLIP + 4) & X86CPU.PFINFO.IP_MASK] << (32 - shift);
this.assert(l === this.getLong(this.regLIP));
this.cbPrefetch -= 4;
return l;
@ -3509,9 +3509,9 @@ X86CPU.prototype.refillPrefetch = function()
if (block) {
var off = regLIP & this.nBlockLimit;
var cbMax = this.nBlockSize - off;
if (cbMax > X86CPU.PREFETCH.LENGTH) cbMax = X86CPU.PREFETCH.LENGTH;
if (cbMax > X86CPU.PFINFO.LENGTH) cbMax = X86CPU.PFINFO.LENGTH;
for (var i = 0; i < cbMax; i += 4) {
this.adwPrefetch[regLIP & X86CPU.PREFETCH.IP_MASK] = block.readLongDirect(off, regLIP);
this.adwPrefetch[regLIP & X86CPU.PFINFO.IP_MASK] = block.readLongDirect(off, regLIP);
off += 4; regLIP += 4;
}
this.cbPrefetch = i - (this.regLIP & 0x3);