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Add The LISP Challenge

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This change introduces a 2.5kb program that's comes pretty close so far
to bootstrapping John McCarthy's metacircular evaluator on bare metal.
This commit is contained in:
Justine Tunney 2020-10-01 01:20:13 -07:00
parent fd22e55b42
commit b6793d42d5
34 changed files with 1056 additions and 358 deletions
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93
tool/build/lib/modrm.c
View file

@ -26,51 +26,7 @@
#include "tool/build/lib/modrm.h"
#include "tool/build/lib/throw.h"
static relegated noinline int64_t ComputeAddressReal(const struct Machine *m,
uint32_t rde, uint8_t *s,
uint64_t i) {
switch (ModrmRm(rde)) {
case 0:
i += Read16(m->bx);
i += Read16(m->si);
break;
case 1:
i += Read16(m->bx);
i += Read16(m->di);
break;
case 2:
s = m->ss;
i += Read16(m->bp);
i += Read16(m->si);
break;
case 3:
s = m->ss;
i += Read16(m->bp);
i += Read16(m->di);
break;
case 4:
i += Read16(m->si);
break;
case 5:
i += Read16(m->di);
break;
case 6:
if (ModrmMod(rde)) {
s = m->ss;
i += Read16(m->bp);
}
break;
case 7:
i += Read16(m->bx);
break;
default:
unreachable;
}
i &= 0xffff;
return AddSegment(m, rde, i, s);
}
int64_t ComputeAddress(const struct Machine *m, uint32_t rde) {
struct AddrSeg LoadEffectiveAddress(const struct Machine *m, uint32_t rde) {
uint8_t *s = m->ds;
uint64_t i = m->xedd->op.disp;
DCHECK(!IsModrmRegister(rde));
@ -100,10 +56,53 @@ int64_t ComputeAddress(const struct Machine *m, uint32_t rde) {
if (Eamode(rde) == XED_MODE_LEGACY) {
i &= 0xffffffff;
}
return AddSegment(m, rde, i, s);
} else {
return ComputeAddressReal(m, rde, s, i);
switch (ModrmRm(rde)) {
case 0:
i += Read16(m->bx);
i += Read16(m->si);
break;
case 1:
i += Read16(m->bx);
i += Read16(m->di);
break;
case 2:
s = m->ss;
i += Read16(m->bp);
i += Read16(m->si);
break;
case 3:
s = m->ss;
i += Read16(m->bp);
i += Read16(m->di);
break;
case 4:
i += Read16(m->si);
break;
case 5:
i += Read16(m->di);
break;
case 6:
if (ModrmMod(rde)) {
s = m->ss;
i += Read16(m->bp);
}
break;
case 7:
i += Read16(m->bx);
break;
default:
unreachable;
}
i &= 0xffff;
}
return (struct AddrSeg){i, s};
}
int64_t ComputeAddress(const struct Machine *m, uint32_t rde) {
struct AddrSeg ea;
ea = LoadEffectiveAddress(m, rde);
return AddSegment(m, rde, ea.addr, ea.seg);
}
void *ComputeReserveAddressRead(struct Machine *m, uint32_t rde, size_t n) {