From 3e39c0a8053b3e960cf4c3aea3c814e7dc97cfd6 Mon Sep 17 00:00:00 2001 From: hjl Date: Sat, 27 Jan 2018 13:10:24 +0000 Subject: [PATCH 03/13] i386: Use const reference of struct ix86_frame to avoid copy We can use const reference of struct ix86_frame to avoid making a local copy of ix86_frame. ix86_expand_epilogue makes a local copy of struct ix86_frame and uses the reg_save_offset field as a local variable. This patch uses a separate local variable for reg_save_offset. Tested on x86-64 with ada. Backport from mainline PR target/83905 * config/i386/i386.c (ix86_expand_prologue): Use cost reference of struct ix86_frame. (ix86_expand_epilogue): Likewise. Add a local variable for the reg_save_offset field in struct ix86_frame. git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/branches/gcc-7-branch@257123 138bc75d-0d04-0410-961f-82ee72b054a4 --- gcc/config/i386/i386.c | 24 ++++++++++++------------ 1 file changed, 12 insertions(+), 12 deletions(-) diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c index 13ebf107e90..6c98f7581e2 100644 --- a/gcc/config/i386/i386.c +++ b/gcc/config/i386/i386.c @@ -12633,7 +12633,6 @@ ix86_expand_prologue (void) { struct machine_function *m = cfun->machine; rtx insn, t; - struct ix86_frame frame; HOST_WIDE_INT allocate; bool int_registers_saved; bool sse_registers_saved; @@ -12657,7 +12656,7 @@ ix86_expand_prologue (void) m->fs.sp_valid = true; ix86_compute_frame_layout (); - frame = m->frame; + const struct ix86_frame &frame = cfun->machine->frame; if (!TARGET_64BIT && ix86_function_ms_hook_prologue (current_function_decl)) { @@ -13329,13 +13328,12 @@ ix86_expand_epilogue (int style) { struct machine_function *m = cfun->machine; struct machine_frame_state frame_state_save = m->fs; - struct ix86_frame frame; bool restore_regs_via_mov; bool using_drap; ix86_finalize_stack_realign_flags (); ix86_compute_frame_layout (); - frame = m->frame; + const struct ix86_frame &frame = cfun->machine->frame; m->fs.sp_valid = (!frame_pointer_needed || (crtl->sp_is_unchanging @@ -13377,11 +13375,13 @@ ix86_expand_epilogue (int style) + UNITS_PER_WORD); } + HOST_WIDE_INT reg_save_offset = frame.reg_save_offset; + /* Special care must be taken for the normal return case of a function using eh_return: the eax and edx registers are marked as saved, but not restored along this path. Adjust the save location to match. */ if (crtl->calls_eh_return && style != 2) - frame.reg_save_offset -= 2 * UNITS_PER_WORD; + reg_save_offset -= 2 * UNITS_PER_WORD; /* EH_RETURN requires the use of moves to function properly. */ if (crtl->calls_eh_return) @@ -13397,11 +13397,11 @@ ix86_expand_epilogue (int style) else if (TARGET_EPILOGUE_USING_MOVE && cfun->machine->use_fast_prologue_epilogue && (frame.nregs > 1 - || m->fs.sp_offset != frame.reg_save_offset)) + || m->fs.sp_offset != reg_save_offset)) restore_regs_via_mov = true; else if (frame_pointer_needed && !frame.nregs - && m->fs.sp_offset != frame.reg_save_offset) + && m->fs.sp_offset != reg_save_offset) restore_regs_via_mov = true; else if (frame_pointer_needed && TARGET_USE_LEAVE @@ -13439,7 +13439,7 @@ ix86_expand_epilogue (int style) rtx t; if (frame.nregs) - ix86_emit_restore_regs_using_mov (frame.reg_save_offset, style == 2); + ix86_emit_restore_regs_using_mov (reg_save_offset, style == 2); /* eh_return epilogues need %ecx added to the stack pointer. */ if (style == 2) @@ -13529,19 +13529,19 @@ ix86_expand_epilogue (int style) epilogues. */ if (!m->fs.sp_valid || (TARGET_SEH - && (m->fs.sp_offset - frame.reg_save_offset + && (m->fs.sp_offset - reg_save_offset >= SEH_MAX_FRAME_SIZE))) { pro_epilogue_adjust_stack (stack_pointer_rtx, hard_frame_pointer_rtx, GEN_INT (m->fs.fp_offset - - frame.reg_save_offset), + - reg_save_offset), style, false); } - else if (m->fs.sp_offset != frame.reg_save_offset) + else if (m->fs.sp_offset != reg_save_offset) { pro_epilogue_adjust_stack (stack_pointer_rtx, stack_pointer_rtx, GEN_INT (m->fs.sp_offset - - frame.reg_save_offset), + - reg_save_offset), style, m->fs.cfa_reg == stack_pointer_rtx); } -- 2.16.3