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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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79
third_party/xed/x86ild.greg.c vendored
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@ -130,8 +130,8 @@ static const struct XedDenseMagnums {
xed_bits_t OSZ_NONTERM_REFINING66_EOSZ[2][2][3];
} kXed = {
.vex_prefix_recoding = {0, 1, 3, 2},
.BRDISPz_BRDISP_WIDTH = {0x00, 0x10, 0x20, 0x20},
.MEMDISPv_DISP_WIDTH = {0x00, 0x10, 0x20, 0x40},
.BRDISPz_BRDISP_WIDTH = {0, 16, 32, 32},
.MEMDISPv_DISP_WIDTH = {0, 16, 32, 64},
.SIMMz_IMM_WIDTH = {0x00, 0x10, 0x20, 0x20},
.UIMMv_IMM_WIDTH = {0x00, 0x10, 0x20, 0x40},
.ASZ_NONTERM_EASZ =
@ -786,6 +786,28 @@ privileged static void xed_evex_scanner(struct XedDecodedInst *d) {
}
}
privileged static uint64_t xed_read_number(uint8_t *p, size_t n, bool s) {
switch (s << 2 | bsr(n)) {
case 0b000:
return *p;
case 0b100:
return (int8_t)*p;
case 0b001:
return READ16LE(p);
case 0b101:
return (int16_t)READ16LE(p);
case 0b010:
return READ32LE(p);
case 0b110:
return (int32_t)READ32LE(p);
case 0b011:
case 0b111:
return READ64LE(p);
default:
unreachable;
}
}
privileged static void xed_evex_imm_scanner(struct XedDecodedInst *d) {
uint64_t uimm0;
uint8_t *itext, *imm_ptr;
@ -829,34 +851,9 @@ privileged static void xed_evex_imm_scanner(struct XedDecodedInst *d) {
return;
}
}
imm_ptr = itext + d->op.pos_imm;
if (imm_bytes) {
switch (d->op.imm_signed << 2 | bsr(imm_bytes)) {
case 0b000:
d->op.uimm0 = *imm_ptr;
break;
case 0b100:
d->op.uimm0 = (int8_t)*imm_ptr;
break;
case 0b001:
d->op.uimm0 = READ16LE(imm_ptr);
break;
case 0b101:
d->op.uimm0 = (int16_t)READ16LE(imm_ptr);
break;
case 0b010:
d->op.uimm0 = READ32LE(imm_ptr);
break;
case 0b110:
d->op.uimm0 = (int32_t)READ32LE(imm_ptr);
break;
case 0b011:
case 0b111:
d->op.uimm0 = READ64LE(imm_ptr);
break;
default:
break;
}
d->op.uimm0 =
xed_read_number(itext + d->op.pos_imm, imm_bytes, d->op.imm_signed);
}
}
@ -1026,6 +1023,7 @@ privileged static void XED_LF_BRDISPz_BRDISP_WIDTH_OSZ_NONTERM_EOSZ_l2(
x->op.disp_width =
kXed.BRDISPz_BRDISP_WIDTH[kXed.OSZ_NONTERM_EOSZ[x->op.rexw][x->op.osz]
[x->op.mode]];
x->op.disp_unsigned = true;
}
privileged static void XED_LF_RESOLVE_BYREG_DISP_map0x0_op0xc7_l1(
@ -1046,6 +1044,7 @@ privileged static void XED_LF_MEMDISPv_DISP_WIDTH_ASZ_NONTERM_EASZ_l2(
struct XedDecodedInst *x) {
x->op.disp_width =
kXed.MEMDISPv_DISP_WIDTH[kXed.ASZ_NONTERM_EASZ[x->op.asz][x->op.mode]];
x->op.disp_unsigned = true;
}
privileged static void XED_LF_BRDISP32_BRDISP_WIDTH_CONST_l2(
@ -1056,15 +1055,14 @@ privileged static void XED_LF_BRDISP32_BRDISP_WIDTH_CONST_l2(
privileged static void XED_LF_DISP_BUCKET_0_l1(struct XedDecodedInst *x) {
if (x->op.mode <= XED_MODE_LEGACY) {
XED_LF_BRDISPz_BRDISP_WIDTH_OSZ_NONTERM_EOSZ_l2(x);
x->op.disp_unsigned = false;
} else if (x->op.mode == XED_MODE_LONG) {
XED_LF_BRDISP32_BRDISP_WIDTH_CONST_l2(x);
}
}
privileged static void xed_disp_scanner(struct XedDecodedInst *d) {
uint8_t *disp_ptr;
xed_bits_t length, disp_width, disp_bytes, max_bytes;
const xed_bits_t ilog2[] = {99, 0, 1, 99, 2, 99, 99, 99, 3};
length = d->length;
if (d->op.map < XED_ILD_MAP2) {
switch (xed_disp_bits_2d[d->op.map][d->op.opcode]) {
@ -1095,23 +1093,8 @@ privileged static void xed_disp_scanner(struct XedDecodedInst *d) {
if (disp_bytes) {
max_bytes = d->op.max_bytes;
if (length + disp_bytes <= max_bytes) {
disp_ptr = d->bytes + length;
switch (ilog2[disp_bytes]) {
case 0:
d->op.disp = *(int8_t *)disp_ptr;
break;
case 1:
d->op.disp = (int16_t)READ16LE(disp_ptr);
break;
case 2:
d->op.disp = (int32_t)READ32LE(disp_ptr);
break;
case 3:
d->op.disp = (int64_t)READ64LE(disp_ptr);
break;
default:
break;
}
d->op.disp =
xed_read_number(d->bytes + length, disp_bytes, !d->op.disp_unsigned);
d->op.pos_disp = length;
d->length = length + disp_bytes;
} else {