ARC: dw2 unwind: add infrastructure for adding cfi pseudo ops to asm
1. detect whether binutils supports the cfi pseudo ops
2. define conditional macros to generate the ops
3. define new ENTRY_CFI/END_CFI to annotate hand asm code.
- Needed because we don't want to emit dwarf info in general ENTRY/END
used by lowest level trap/exception/interrutp handlers as unwinder
gets confused trying to unwind out of them. We want unwinder to
instead stop when it hits onfo those routines
- These provide minimal start/end cfi ops assuming routine doesn't
touch stack memory/regs
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
diff --git a/arch/arc/Makefile b/arch/arc/Makefile
index a2a6a46..aa82d13 100644
--- a/arch/arc/Makefile
+++ b/arch/arc/Makefile
@@ -65,7 +65,8 @@
endif
-cflags-$(CONFIG_ARC_DW2_UNWIND) += -fasynchronous-unwind-tables
+cfi := $(call as-instr,.cfi_startproc\n.cfi_endproc,-DARC_DW2_UNWIND_AS_CFI)
+cflags-$(CONFIG_ARC_DW2_UNWIND) += -fasynchronous-unwind-tables $(cfi)
ifndef CONFIG_CC_OPTIMIZE_FOR_SIZE
# Generic build system uses -O2, we want -O3