From 8480a37e146c40e82a93c0ecf6144571516c95c5 Mon Sep 17 00:00:00 2001 From: Simon Marchi Date: Mon, 19 Feb 2024 13:07:47 -0500 Subject: gdb: pass frames as `const frame_info_ptr &` We currently pass frames to function by value, as `frame_info_ptr`. This is somewhat expensive: - the size of `frame_info_ptr` is 64 bytes, which is a bit big to pass by value - the constructors and destructor link/unlink the object in the global `frame_info_ptr::frame_list` list. This is an `intrusive_list`, so it's not so bad: it's just assigning a few points, there's no memory allocation as if it was `std::list`, but still it's useless to do that over and over. As suggested by Tom Tromey, change many function signatures to accept `const frame_info_ptr &` instead of `frame_info_ptr`. Some functions reassign their `frame_info_ptr` parameter, like: void the_func (frame_info_ptr frame) { for (; frame != nullptr; frame = get_prev_frame (frame)) { ... } } I wondered what to do about them, do I leave them as-is or change them (and need to introduce a separate local variable that can be re-assigned). I opted for the later for consistency. It might not be clear why some functions take `const frame_info_ptr &` while others take `frame_info_ptr`. Also, if a function took a `frame_info_ptr` because it did re-assign its parameter, I doubt that we would think to change it to `const frame_info_ptr &` should the implementation change such that it doesn't need to take `frame_info_ptr` anymore. It seems better to have a simple rule and apply it everywhere. Change-Id: I59d10addef687d157f82ccf4d54f5dde9a963fd0 Approved-By: Andrew Burgess --- gdb/sparc-netbsd-tdep.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) (limited to 'gdb/sparc-netbsd-tdep.c') diff --git a/gdb/sparc-netbsd-tdep.c b/gdb/sparc-netbsd-tdep.c index 486381f..d2b1a4b 100644 --- a/gdb/sparc-netbsd-tdep.c +++ b/gdb/sparc-netbsd-tdep.c @@ -95,7 +95,7 @@ sparc32nbsd_pc_in_sigtramp (CORE_ADDR pc, const char *name) } trad_frame_saved_reg * -sparc32nbsd_sigcontext_saved_regs (frame_info_ptr this_frame) +sparc32nbsd_sigcontext_saved_regs (const frame_info_ptr &this_frame) { struct gdbarch *gdbarch = get_frame_arch (this_frame); trad_frame_saved_reg *saved_regs; @@ -180,7 +180,7 @@ sparc32nbsd_sigcontext_saved_regs (frame_info_ptr this_frame) } static struct sparc_frame_cache * -sparc32nbsd_sigcontext_frame_cache (frame_info_ptr this_frame, +sparc32nbsd_sigcontext_frame_cache (const frame_info_ptr &this_frame, void **this_cache) { struct sparc_frame_cache *cache; @@ -211,7 +211,7 @@ sparc32nbsd_sigcontext_frame_cache (frame_info_ptr this_frame, } static void -sparc32nbsd_sigcontext_frame_this_id (frame_info_ptr this_frame, +sparc32nbsd_sigcontext_frame_this_id (const frame_info_ptr &this_frame, void **this_cache, struct frame_id *this_id) { @@ -222,7 +222,7 @@ sparc32nbsd_sigcontext_frame_this_id (frame_info_ptr this_frame, } static struct value * -sparc32nbsd_sigcontext_frame_prev_register (frame_info_ptr this_frame, +sparc32nbsd_sigcontext_frame_prev_register (const frame_info_ptr &this_frame, void **this_cache, int regnum) { struct sparc_frame_cache *cache = @@ -233,7 +233,7 @@ sparc32nbsd_sigcontext_frame_prev_register (frame_info_ptr this_frame, static int sparc32nbsd_sigcontext_frame_sniffer (const struct frame_unwind *self, - frame_info_ptr this_frame, + const frame_info_ptr &this_frame, void **this_cache) { CORE_ADDR pc = get_frame_pc (this_frame); @@ -264,7 +264,7 @@ static const struct frame_unwind sparc32nbsd_sigcontext_frame_unwind = address. */ CORE_ADDR -sparcnbsd_step_trap (frame_info_ptr frame, unsigned long insn) +sparcnbsd_step_trap (const frame_info_ptr &frame, unsigned long insn) { if ((X_I (insn) == 0 && X_RS1 (insn) == 0 && X_RS2 (insn) == 0) || (X_I (insn) == 1 && X_RS1 (insn) == 0 && (insn & 0x7f) == 0)) -- cgit v1.1