Hi Christophe,
On 5/15/19 1:39 PM, Christophe Lyon wrote:
Without this, when we are unwinding across a signal frame we can jump
to an even address which leads to an exception.
This is needed in __gnu_persnality_sigframe_fdpic() when restoring the
PC from the signal frame since the PC saved by the kernel has the LSB
bit set to zero.
2019-XX-XX Christophe Lyon <christophe.l...@st.com>
Mickaël Guêné <mickael.gu...@st.com>
libgcc/
* config/arm/unwind-arm.c (_Unwind_VRS_Set): Handle v7m
architecture.
Change-Id: Ie84de548226bcf1751e19a09e8f091fb3013ccea
diff --git a/libgcc/config/arm/unwind-arm.c
b/libgcc/config/arm/unwind-arm.c
index 9ba73e7..ba47150 100644
--- a/libgcc/config/arm/unwind-arm.c
+++ b/libgcc/config/arm/unwind-arm.c
@@ -199,6 +199,11 @@ _Unwind_VRS_Result _Unwind_VRS_Set
(_Unwind_Context *context,
return _UVRSR_FAILED;
vrs->core.r[regno] = *(_uw *) valuep;
+#if defined(__ARM_ARCH_7M__)
+ /* Force LSB bit since we always run thumb code. */
+ if (regno == 15)
+ vrs->core.r[regno] |= 1;
+#endif
Hmm, this looks quite specific. There are other architectures that are
thumb-only too (6-M, 7E-M etc).
Would checking for __thumb__ be better?
Thanks,
Kyrill
return _UVRSR_OK;
case _UVRSC_VFP:
--
2.6.3
