gh-mirror/mikepaul-LuaJIT
1
0
Fork 0
mirror of https://github.com/LuaJIT/LuaJIT.git synced 2025-02-07 15:14:08 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

MIPS: Use precise search for exit jump patching.

Browse Source 
Contributed by Djordje Kovacevic and Stefan Pejic.
This commit is contained in:
Mike Pall 2017-06-07 19:16:22 +02:00
parent 630ff3196a
commit 7381b62035
1 changed files with 5 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
src/lj_asm_mips.h
View File

@ -1933,7 +1933,11 @@ void lj_asm_patchexit(jit_State *J, GCtrace *T, ExitNo exitno, MCode *target)
MCode tjump = MIPSI_J|(((uintptr_t)target>>2)&0x03ffffffu);
for (p++; p < pe; p++) {
if (*p == exitload) { /* Look for load of exit number. */
if (((p[-1] ^ (px-p)) & 0xffffu) == 0) { /* Look for exitstub branch. */
/* Look for exitstub branch. Yes, this covers all used branch variants. */
if (((p[-1] ^ (px-p)) & 0xffffu) == 0 &&
((p[-1] & 0xf0000000u) == MIPSI_BEQ ||
(p[-1] & 0xfc1e0000u) == MIPSI_BLTZ ||
(p[-1] & 0xffe00000u) == MIPSI_BC1F)) {
ptrdiff_t delta = target - p;
if (((delta + 0x8000) >> 16) == 0) { /* Patch in-range branch. */
patchbranch: