unwind: repair register restoration for OR1K
Currently, OR1K architecture put the program counter at offset 0x128 of
the current `or1k_thread_state_t`. However, the PC is restored after
updating the thread pointer in `r3`, which causes the PC to be fetched
incorrectly.
This patch swaps the order of restoration of `r9` and `r3`, such that
the PC is restored to `r9` using the current thread state.
Patch by Oi Chee Cheung!
Reviewed By: whitequark, compnerd
Differential Revision: https://reviews.llvm.org/D107042
GitOrigin-RevId: d6d0b6559e97a3d0b258814e870d3e19f3a7ffcc
diff --git a/src/UnwindRegistersRestore.S b/src/UnwindRegistersRestore.S
index d8bf1ad..c2106f3 100644
--- a/src/UnwindRegistersRestore.S
+++ b/src/UnwindRegistersRestore.S
@@ -800,11 +800,12 @@
l.lwz r30,120(r3)
l.lwz r31,124(r3)
+ # load new pc into ra
+ l.lwz r9, 128(r3)
+
# at last, restore r3
l.lwz r3, 12(r3)
- # load new pc into ra
- l.lwz r9, 128(r3)
# jump to pc
l.jr r9
l.nop
