tcg/arm: Return false on failure from patch_reloc

This does require an extra two checks within the slow paths
to replace the assert that we're moving.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This commit is contained in:
Richard Henderson 2018-11-30 13:01:57 -08:00
parent 214bfe83d5
commit 43fabd30e2
1 changed files with 16 additions and 6 deletions

View File

@ -187,10 +187,14 @@ static const uint8_t tcg_cond_to_arm_cond[] = {
[TCG_COND_GTU] = COND_HI,
};
static inline void reloc_pc24(tcg_insn_unit *code_ptr, tcg_insn_unit *target)
static inline bool reloc_pc24(tcg_insn_unit *code_ptr, tcg_insn_unit *target)
{
ptrdiff_t offset = (tcg_ptr_byte_diff(target, code_ptr) - 8) >> 2;
*code_ptr = (*code_ptr & ~0xffffff) | (offset & 0xffffff);
if (offset == sextract32(offset, 0, 24)) {
*code_ptr = (*code_ptr & ~0xffffff) | (offset & 0xffffff);
return true;
}
return false;
}
static bool patch_reloc(tcg_insn_unit *code_ptr, int type,
@ -199,7 +203,7 @@ static bool patch_reloc(tcg_insn_unit *code_ptr, int type,
tcg_debug_assert(addend == 0);
if (type == R_ARM_PC24) {
reloc_pc24(code_ptr, (tcg_insn_unit *)value);
return reloc_pc24(code_ptr, (tcg_insn_unit *)value);
} else if (type == R_ARM_PC13) {
intptr_t diff = value - (uintptr_t)(code_ptr + 2);
tcg_insn_unit insn = *code_ptr;
@ -213,7 +217,11 @@ static bool patch_reloc(tcg_insn_unit *code_ptr, int type,
} else {
int rd = extract32(insn, 12, 4);
int rt = rd == TCG_REG_PC ? TCG_REG_TMP : rd;
assert(diff >= 0x1000 && diff < 0x100000);
if (diff < 0x1000 || diff >= 0x100000) {
return false;
}
/* add rt, pc, #high */
*code_ptr++ = ((insn & 0xf0000000) | (1 << 25) | ARITH_ADD
| (TCG_REG_PC << 16) | (rt << 12)
@ -1372,7 +1380,8 @@ static void tcg_out_qemu_ld_slow_path(TCGContext *s, TCGLabelQemuLdst *lb)
TCGMemOp opc = get_memop(oi);
void *func;
reloc_pc24(lb->label_ptr[0], s->code_ptr);
bool ok = reloc_pc24(lb->label_ptr[0], s->code_ptr);
tcg_debug_assert(ok);
argreg = tcg_out_arg_reg32(s, TCG_REG_R0, TCG_AREG0);
if (TARGET_LONG_BITS == 64) {
@ -1432,7 +1441,8 @@ static void tcg_out_qemu_st_slow_path(TCGContext *s, TCGLabelQemuLdst *lb)
TCGMemOpIdx oi = lb->oi;
TCGMemOp opc = get_memop(oi);
reloc_pc24(lb->label_ptr[0], s->code_ptr);
bool ok = reloc_pc24(lb->label_ptr[0], s->code_ptr);
tcg_debug_assert(ok);
argreg = TCG_REG_R0;
argreg = tcg_out_arg_reg32(s, argreg, TCG_AREG0);