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Added a temporary fix to PUSH operations to ensure that 16-bit pushes wrap around 64K boundaries (TODO: a 16-bit PUSH at offset 0x0001 or a POP at offset 0xFFFF must either wrap or fault as appropriate)

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Jeff Parsons 2017-07-19 23:24:18 -07:00 • committed by Jeff Parsons
commit 308bd75af4
10 changed files with 205 additions and 184 deletions
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4
modules/pcx86/lib/x86cpu.js
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@ -3836,7 +3836,7 @@ class X86CPU extends CPU {
* if the result is negative, we need only be concerned if the signs of both numbers are the same
* (ie, the sign of their XOR'ed union is positive).
*/
if (((regLSP - this.regLSPLimitLow)|0) < 0 && (this.regLSPLimitLow ^ regLSP) >= 0) {
if (((regLSP - this.regLSPLimitLow)|0) < 0 && (this.regLSPLimitLow ^ this.regLSP) >= 0) {
/*
* There's no such thing as an SS fault on the 8086/8088, and I'm assuming that, on newer
* processors, when the stack segment limit is set to the maximum, it's OK for the stack to wrap.
@ -3897,7 +3897,7 @@ class X86CPU extends CPU {
* if the result is negative, we need only be concerned if the signs of both numbers are the same
* (ie, the sign of their XOR'ed union is positive).
*/
if (((regLSP - this.regLSPLimitLow)|0) < 0 && (this.regLSPLimitLow ^ regLSP) >= 0) {
if (((regLSP - this.regLSPLimitLow)|0) < 0 && (this.regLSPLimitLow ^ this.regLSP) >= 0) {
/*
* There's no such thing as an SS fault on the 8086/8088, and I'm assuming that, on newer
* processors, when the stack segment limit is set to the maximum, it's OK for the stack to wrap.