cosmopolitan/test/tool/build/lib/modrm_test.c
2020-12-27 17:18:44 -08:00

111 lines
5.9 KiB
C

/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8 :vi│
╞══════════════════════════════════════════════════════════════════════════════╡
│ Copyright 2020 Justine Alexandra Roberts Tunney │
│ │
│ Permission to use, copy, modify, and/or distribute this software for │
│ any purpose with or without fee is hereby granted, provided that the │
│ above copyright notice and this permission notice appear in all copies. │
│ │
│ THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL │
│ WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED │
│ WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE │
│ AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL │
│ DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR │
│ PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER │
│ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR │
│ PERFORMANCE OF THIS SOFTWARE. │
╚─────────────────────────────────────────────────────────────────────────────*/
#include "libc/mem/mem.h"
#include "libc/runtime/gc.h"
#include "libc/testlib/testlib.h"
#include "third_party/xed/x86.h"
#include "tool/build/lib/endian.h"
#include "tool/build/lib/machine.h"
#include "tool/build/lib/modrm.h"
TEST(modrm, testAddressSizeOverride_isNotPresent_keepsWholeExpression) {
struct Machine *m = gc(NewMachine());
struct XedDecodedInst *xedd = gc(calloc(1, sizeof(struct XedDecodedInst)));
uint8_t op[] = {0x8d, 0x04, 0x03}; /* lea (%rbx,%rax,1),%eax */
m->xedd = xedd;
Write64(m->bx, 0x2);
Write64(m->ax, 0xffffffff);
xed_decoded_inst_zero_set_mode(xedd, XED_MACHINE_MODE_LONG_64);
ASSERT_EQ(0, xed_instruction_length_decode(xedd, op, sizeof(op)));
EXPECT_EQ(0x100000001, ComputeAddress(m, m->xedd->op.rde));
}
TEST(modrm, testAddressSizeOverride_isPresent_modulesWholeExpression) {
struct Machine *m = gc(NewMachine());
struct XedDecodedInst *xedd = gc(calloc(1, sizeof(struct XedDecodedInst)));
uint8_t op[] = {0x67, 0x8d, 0x04, 0x03}; /* lea (%ebx,%eax,1),%eax */
m->xedd = xedd;
Write64(m->bx, 0x2);
Write64(m->ax, 0xffffffff);
xed_decoded_inst_zero_set_mode(xedd, XED_MACHINE_MODE_LONG_64);
ASSERT_EQ(0, xed_instruction_length_decode(xedd, op, sizeof(op)));
EXPECT_EQ(0x000000001, ComputeAddress(m, m->xedd->op.rde));
}
TEST(modrm, testOverflow_doesntTriggerTooling) {
struct Machine *m = gc(NewMachine());
struct XedDecodedInst *xedd = gc(calloc(1, sizeof(struct XedDecodedInst)));
uint8_t op[] = {0x8d, 0x04, 0x03}; /* lea (%rbx,%rax,1),%eax */
m->xedd = xedd;
Write64(m->bx, 0x0000000000000001);
Write64(m->ax, 0x7fffffffffffffff);
xed_decoded_inst_zero_set_mode(xedd, XED_MACHINE_MODE_LONG_64);
ASSERT_EQ(0, xed_instruction_length_decode(xedd, op, sizeof(op)));
EXPECT_EQ(0x8000000000000000ull,
(uint64_t)ComputeAddress(m, m->xedd->op.rde));
}
TEST(modrm, testPuttingOnTheRiz) {
struct Machine *m = gc(NewMachine());
static uint8_t ops[][15] = {
{0x8d, 0b00110100, 0b00100110}, // lea (%rsi),%esi
{0x67, 0x8d, 0b00110100, 0b11100110}, // lea (%esi,%eiz,8),%esi
{103, 141, 180, 229, 55, 19, 3, 0}, // lea 0x31337(%ebp,%eiz,8),%esi
{141, 52, 229, 55, 19, 3, 0}, // lea 0x31337,%esi
};
m->xedd = gc(calloc(1, sizeof(struct XedDecodedInst)));
Write64(m->si, 0x100000001);
Write64(m->bp, 0x200000002);
xed_decoded_inst_zero_set_mode(m->xedd, XED_MACHINE_MODE_LONG_64);
ASSERT_EQ(0, xed_instruction_length_decode(m->xedd, ops[0], sizeof(ops[0])));
EXPECT_EQ(0x100000001, ComputeAddress(m, m->xedd->op.rde));
xed_decoded_inst_zero_set_mode(m->xedd, XED_MACHINE_MODE_LONG_64);
ASSERT_EQ(0, xed_instruction_length_decode(m->xedd, ops[1], sizeof(ops[1])));
EXPECT_EQ(0x000000001, ComputeAddress(m, m->xedd->op.rde));
xed_decoded_inst_zero_set_mode(m->xedd, XED_MACHINE_MODE_LONG_64);
ASSERT_EQ(0, xed_instruction_length_decode(m->xedd, ops[2], sizeof(ops[2])));
EXPECT_EQ(0x31339, ComputeAddress(m, m->xedd->op.rde));
xed_decoded_inst_zero_set_mode(m->xedd, XED_MACHINE_MODE_LONG_64);
ASSERT_EQ(0, xed_instruction_length_decode(m->xedd, ops[3], sizeof(ops[3])));
EXPECT_EQ(0x31337, ComputeAddress(m, m->xedd->op.rde));
}
TEST(modrm, testSibIndexOnly) {
// lea 0x0(,%rcx,4),%r8
// mod = 0b00 (0)
// reg = 0b000 (0)
// rm = 0b100 (4)
// scale = 0b10 (2)
// index = 0b001 (1)
// base = 0b101 (5)
struct Machine *m = gc(NewMachine());
struct XedDecodedInst *xedd = gc(calloc(1, sizeof(struct XedDecodedInst)));
uint8_t op[] = {0x4c, 0x8d, 0x04, 0x8d, 0, 0, 0, 0};
m->xedd = xedd;
Write64(m->bp, 0x123);
Write64(m->cx, 0x123);
xed_decoded_inst_zero_set_mode(xedd, XED_MACHINE_MODE_LONG_64);
ASSERT_EQ(0, xed_instruction_length_decode(xedd, op, sizeof(op)));
EXPECT_TRUE(Rexw(m->xedd->op.rde));
EXPECT_TRUE(Rexr(m->xedd->op.rde));
EXPECT_FALSE(Rexb(m->xedd->op.rde));
EXPECT_EQ(0b000, ModrmReg(m->xedd->op.rde));
EXPECT_EQ(0b100, ModrmRm(m->xedd->op.rde));
EXPECT_EQ(0x123 * 4, (uint64_t)ComputeAddress(m, m->xedd->op.rde));
}