Hi Richard, Ramana,
Attached is a small fix for resolving a g++.old-deja/g++.jason/thunk2.C
regression we found under a TARGET_THUMB1_ONLY multilib (-mthumb
-march=armv6-m to be exact). Basically under those conditions, the thunk
is in Thumb mode, so the subtraction should be 4 rather than 8.
Original patch was by Julian, with trivial adaptations for trunk by me.
We've been carrying this fix for a while by now. Okay for trunk? (and
stable branches?)
Thanks,
Chung-Lin
2014-06-08 Julian Brown <jul...@codesourcery.com>
Chung-Lin Tang <clt...@codesourcery.com>
* config/arm/arm.c (arm_output_mi_thunk): Fix offset for
TARGET_THUMB1_ONLY. Add comments.
Index: config/arm/arm.c
===================================================================
--- config/arm/arm.c (revision 211353)
+++ config/arm/arm.c (working copy)
@@ -28428,9 +28428,13 @@ arm_output_mi_thunk (FILE *file, tree thunk ATTRIB
fputs (":\n", file);
if (flag_pic)
{
- /* Output ".word .LTHUNKn-7-.LTHUNKPCn". */
+ /* Output ".word .LTHUNKn-[37]-.LTHUNKPCn". */
rtx tem = XEXP (DECL_RTL (function), 0);
- tem = plus_constant (GET_MODE (tem), tem, -7);
+ /* For TARGET_THUMB1_ONLY the thunk is in Thumb mode, so the PC
+ pipeline offset is four rather than eight. Adjust the offset
+ accordingly. */
+ tem = plus_constant (GET_MODE (tem), tem,
+ TARGET_THUMB1_ONLY ? -3 : -7);
tem = gen_rtx_MINUS (GET_MODE (tem),
tem,
gen_rtx_SYMBOL_REF (Pmode,
