diff options
Diffstat (limited to 'gcc/builtins.c')
| -rw-r--r-- | gcc/builtins.c | 36 |
1 files changed, 22 insertions, 14 deletions
diff --git a/gcc/builtins.c b/gcc/builtins.c index 7c6318e..e4846c8 100644 --- a/gcc/builtins.c +++ b/gcc/builtins.c @@ -910,18 +910,27 @@ expand_builtin_setjmp_receiver (rtx receiver_label ATTRIBUTE_UNUSED) #ifdef HAVE_nonlocal_goto if (! HAVE_nonlocal_goto) #endif - /* First adjust our frame pointer to its actual value. It was - previously set to the start of the virtual area corresponding to - the stacked variables when we branched here and now needs to be - adjusted to the actual hardware fp value. - - Assignments to virtual registers are converted by - instantiate_virtual_regs into the corresponding assignment - to the underlying register (fp in this case) that makes - the original assignment true. - So the following insn will actually be decrementing fp by - STARTING_FRAME_OFFSET. */ - emit_move_insn (virtual_stack_vars_rtx, hard_frame_pointer_rtx); + { + /* First adjust our frame pointer to its actual value. It was + previously set to the start of the virtual area corresponding to + the stacked variables when we branched here and now needs to be + adjusted to the actual hardware fp value. + + Assignments to virtual registers are converted by + instantiate_virtual_regs into the corresponding assignment + to the underlying register (fp in this case) that makes + the original assignment true. + So the following insn will actually be decrementing fp by + STARTING_FRAME_OFFSET. */ + emit_move_insn (virtual_stack_vars_rtx, hard_frame_pointer_rtx); + + /* Restoring the frame pointer also modifies the hard frame pointer. + Mark it used (so that the previous assignment remains live once + the frame pointer is eliminated) and clobbered (to represent the + implicit update from the assignment). */ + emit_use (hard_frame_pointer_rtx); + emit_clobber (hard_frame_pointer_rtx); + } #if !HARD_FRAME_POINTER_IS_ARG_POINTER if (fixed_regs[ARG_POINTER_REGNUM]) @@ -965,8 +974,7 @@ expand_builtin_setjmp_receiver (rtx receiver_label ATTRIBUTE_UNUSED) /* We must not allow the code we just generated to be reordered by scheduling. Specifically, the update of the frame pointer must - happen immediately, not later. Similarly, we must block - (frame-related) register values to be used across this code. */ + happen immediately, not later. */ emit_insn (gen_blockage ()); } |