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BR 2148448: Fix RIP-relative addressing with an immediate

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When there is an immediate in the instruction, a RIP-relative offset
may not be relative to the end of the offset itself, since it is
relative to the end of the *instruction*, not the end of the *offset*.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
This commit is contained in:
H. Peter Anvin 2008-10-06 19:11:07 -07:00
parent a9ed99bddf
commit 9f8171317d
2 changed files with 22 additions and 6 deletions
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17
assemble.c
View File

@ -796,7 +796,7 @@ static bool is_sbyte64(operand *o)
return v >= -128 && v <= 127;
}
static int64_t calcsize(int32_t segment, int64_t offset, int bits,
insn * ins, const uint8_t *codes)
insn * ins, const uint8_t *codes)
{
int64_t length = 0;
uint8_t c;
@ -1777,6 +1777,7 @@ static void gencode(int32_t segment, int64_t offset, int bits,
int32_t rflags;
uint8_t *p;
int32_t s;
enum out_type type;
if (c <= 0177) {
/* pick rfield from operand b */
@ -1840,12 +1841,16 @@ static void gencode(int32_t segment, int64_t offset, int bits,
case 4:
data = ins->oprs[(c >> 3) & 7].offset;
warn_overflow(ea_data.bytes, opx);
out(offset, segment, &data,
ea_data.rip ? OUT_REL4ADR : OUT_ADDRESS,
ea_data.bytes,
ins->oprs[(c >> 3) & 7].segment,
ins->oprs[(c >> 3) & 7].wrt);
s += ea_data.bytes;
if (ea_data.rip) {
data -= insn_end - (offset+ea_data.bytes);
type = OUT_REL4ADR;
} else {
type = OUT_ADDRESS;
}
out(offset, segment, &data, type, ea_data.bytes,
ins->oprs[(c >> 3) & 7].segment,
ins->oprs[(c >> 3) & 7].wrt);
break;
}
offset += s;

11
test/riprel2.asm Normal file
View File

@ -0,0 +1,11 @@
;Testname=unoptimized; Arguments=-fbin -oriprel2.bin -O0; Files=stdout stderr riprel.bin
;Testname=optimized; Arguments=-fbin -oriprel2.bin -Ox; Files=stdout stderr riprel.bin
bits 64
default rel
mov dword [foo],12345678h
mov qword [foo],12345678h
mov [foo],rax
mov dword [foo],12345678h
foo: