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New Debugger command to dump Bus memory allocations

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This commit is contained in:
Jeff Parsons 2015-04-08 09:45:13 -07:00 • committed by jeffpar
commit fa88aa6a2d
9 changed files with 316 additions and 72 deletions
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39
modules/pcjs/lib/x86func.js
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@ -1130,9 +1130,9 @@ X86.fnLFS = function LFS(dst, src)
*
* op=0x0F,0x01,reg=0x2 (GRP7:LGDT)
*
* The 80286 LGDT instruction expects a 40-bit operand: a 16-bit limit, followed by a 24-bit address;
* the ModRM decoder has already supplied the first word of the operand (in dst), which corresponds to the
* limit, so we must fetch the remaining 24 bits ourselves.
* The 80286 LGDT instruction expects a 40-bit operand: a 16-bit limit, followed by a 24-bit address
* (or a 32-bit address in 32-bit mode); the ModRM decoder has already supplied the first word of the
* operand (in dst), which corresponds to the limit, so we must fetch the remaining bits ourselves.
*
* @this {X86CPU}
* @param {number} dst
@ -1144,7 +1144,11 @@ X86.fnLGDT = function LGDT(dst, src)
if (this.regEA === X86.ADDR_INVALID) {
X86.opInvalid.call(this);
} else {
this.addrGDT = this.getShort(this.regEA + 2) | (this.getByte(this.regEA + 4) << 16);
/*
* It shouldn't hurt to always fetch 32 bits of physical memory, which we'll then
* mask with either a 24-bit or a 32-bit mask.
*/
this.addrGDT = this.getLong(this.regEA + 2) & (this.dataMask | (this.dataMask << 8));
this.addrGDTLimit = this.addrGDT + dst;
this.opFlags |= X86.OPFLAG.NOWRITE;
this.nStepCycles -= 11;
@ -1176,9 +1180,9 @@ X86.fnLGS = function LGS(dst, src)
*
* op=0x0F,0x01,reg=0x3 (GRP7:LIDT)
*
* The 80286 LIDT instruction expects a 40-bit operand: a 16-bit limit, followed by a 24-bit address;
* the ModRM decoder has already supplied the first word of the operand (in dst), which corresponds to the
* limit, so we must fetch the remaining 24 bits ourselves.
* The 80286 LIDT instruction expects a 40-bit operand: a 16-bit limit, followed by a 24-bit address
* (or a 32-bit address in 32-bit mode); the ModRM decoder has already supplied the first word of the
* operand (in dst), which corresponds to the limit, so we must fetch the remaining bits ourselves.
*
* @this {X86CPU}
* @param {number} dst
@ -1190,7 +1194,11 @@ X86.fnLIDT = function LIDT(dst, src)
if (this.regEA === X86.ADDR_INVALID) {
X86.opInvalid.call(this);
} else {
this.addrIDT = this.getShort(this.regEA + 2) | (this.getByte(this.regEA + 4) << 16);
/*
* It shouldn't hurt to always fetch 32 bits of physical memory, which we'll then
* mask with either a 24-bit or a 32-bit mask.
*/
this.addrIDT = this.getLong(this.regEA + 2) & (this.dataMask | (this.dataMask << 8));
this.addrIDTLimit = this.addrIDT + dst;
this.opFlags |= X86.OPFLAG.NOWRITE;
this.nStepCycles -= 12;
@ -2182,7 +2190,6 @@ X86.fnSGDT = function SGDT(dst, src)
* calls us does that automatically with the value we return (dst).
*/
dst = this.addrGDTLimit - this.addrGDT;
this.setShort(this.regEA + 2, this.addrGDT);
/*
* We previously left the 6th byte of the target operand "undefined". But it turns out we have to set
* it to *something*, because there's processor detection in PC-DOS 7.0 (at least in the SETUP portion)
@ -2211,12 +2218,10 @@ X86.fnSGDT = function SGDT(dst, src)
* 145E:4BC2 9D POPF
* 145E:4BC3 CB RETF
*
* This code is expecting SGDT on an 80286 to set the 6th "undefined" byte to 0xFF. So we use setShort()
* instead of setByte() and force the upper byte to 0xFF.
*
* TODO: Remove the 0xFF00 below on post-80286 processors; also, determine whether this behavior is unique to real-mode.
* This code is expecting SGDT on an 80286 to set the 6th "undefined" byte to 0xFF.
*/
this.setShort(this.regEA + 4, 0xFF00 | (this.addrGDT >> 16));
var addr = this.addrGDT | (this.model == X86.MODEL_80286? 0xff000000 : 0);
this.setLong(this.regEA + 2, addr);
this.nStepCycles -= 11;
}
return dst;
@ -2522,14 +2527,12 @@ X86.fnSIDT = function SIDT(dst, src)
* us does that automatically with the value we return (dst).
*/
dst = this.addrIDTLimit - this.addrIDT;
this.setShort(this.regEA + 2, this.addrIDT);
/*
* As with SGDT, the 6th byte is technically "undefined" on an 80286, but we now set it to 0xFF, for the
* same reasons discussed in SGDT (above).
*
* TODO: Remove the 0xFF00 below on post-80286 processors; also, determine whether this behavior is unique to real-mode.
*/
this.setShort(this.regEA + 4, 0xFF00 | (this.addrIDT >> 16));
var addr = this.addrIDT | (this.model == X86.MODEL_80286? 0xff000000 : 0);
this.setLong(this.regEA + 2, addr);
this.nStepCycles -= 12;
}
return dst;