Yao Qi 1b451dda5f [ARM] Make thumb2_breakpoint static again ... This patch makes thumb2_breakpoint static. When writing this patch, I find the only reason we keep thumb2_breakpoint extern is that it is used as an argument passed to arm_gdbserver_get_next_pcs. However, field arm_thumb2_breakpoint is only used in a null check in thumb_get_next_pcs_raw, so I wonder why do need to pass thumb2_breakpoint to arm_gdbserver_get_next_pcs. thumb2_breakpoint was added by Daniel Jacobowitz in order to support single-step IT block https://sourceware.org/ml/gdb-patches/2010-01/msg00624.html the logic there was if we have 32-bit thumb-2 breakpoint defined, we can safely single-step IT block, otherwise, we can't. Daniel didn't want to use 16-bit thumb BKPT instruction, because it triggers even on instruction which should be executed. Secondly, using 16-bit thumb illegal instruction on top of 32-bit thumb instruction may break the meaning of original IT blocks, because the other 16-bit can be regarded as an instruction. See more explanations from Daniel's kernel patch http://www.spinics.net/lists/arm-kernel/msg80476.html Let us back to this patch, GDB/GDBserver can safely single step IT block if thumb2_breakpoint is defined, but the single step logic doesn't have to know the thumb-2 breakpoint instruction. Only breakpoint insertion mechanism decides to use which breakpoint instruction. In the software single step code, instead of pass thumb2_breakpoint, we can pass a boolean variable has_thumb2_breakpoint indicate whether the target has thumb-2 breakpoint defined, which is equivalent to the original code. Regression tested on arm-linux. No regression. gdb: 2016-01-14 Yao Qi <yao.qi@linaro.org> * arch/arm-get-next-pcs.c (arm_get_next_pcs_ctor): Change argument arm_thumb2_breakpoint to has_thumb2_breakpoint. (thumb_get_next_pcs_raw): Check has_thumb2_breakpoint instead. * arch/arm-get-next-pcs.h (struct arm_get_next_pcs) <arm_thumb2_breakpoint>: Remove. <has_thumb2_breakpoint>: New field. (arm_get_next_pcs_ctor): Update declaration. * arm-linux-tdep.c (arm_linux_software_single_step): Pass 1 to arm_get_next_pcs_ctor. * arm-tdep.c (arm_software_single_step): Pass 0 to arm_get_next_pcs_ctor. gdb/gdbserver: 2016-01-14 Yao Qi <yao.qi@linaro.org> * linux-aarch32-low.c (thumb2_breakpoint): Make it static. * linux-aarch32-low.h (thumb2_breakpoint): Remove declaration. * linux-arm-low.c (arm_gdbserver_get_next_pcs): Pass 1 to arm_get_next_pcs_ctor.		2016-01-14 09:36:43 +00:00
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aarch64-insn.c	GDB copyright headers update after running GDB's copyright.py script.	2016-01-01 08:43:22 +04:00
aarch64-insn.h	GDB copyright headers update after running GDB's copyright.py script.	2016-01-01 08:43:22 +04:00
arm-get-next-pcs.c	[ARM] Make thumb2_breakpoint static again	2016-01-14 09:36:43 +00:00
arm-get-next-pcs.h	[ARM] Make thumb2_breakpoint static again	2016-01-14 09:36:43 +00:00
arm-linux.c	GDB copyright headers update after running GDB's copyright.py script.	2016-01-01 08:43:22 +04:00
arm-linux.h	GDB copyright headers update after running GDB's copyright.py script.	2016-01-01 08:43:22 +04:00
arm.c	GDB copyright headers update after running GDB's copyright.py script.	2016-01-01 08:43:22 +04:00
arm.h	GDB copyright headers update after running GDB's copyright.py script.	2016-01-01 08:43:22 +04:00
xtensa.h	GDB copyright headers update after running GDB's copyright.py script.	2016-01-01 08:43:22 +04:00