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| author | Jeff Law <law@gcc.gnu.org> | 1997-06-30 14:56:46 -0600 |
|---|---|---|
| committer | Jeff Law <law@gcc.gnu.org> | 1997-06-30 14:56:46 -0600 |
| commit | 07f5b9aa23b577dd5e3de82b71e7d66e148a3888 (patch) | |
| tree | 208b58dc160635d6aff80f09c0caef15f527bcda | |
| parent | 38c1f2d7e6de970a7345b7d7fabe3952f2f7af89 (diff) | |
| download | gcc-07f5b9aa23b577dd5e3de82b71e7d66e148a3888.zip gcc-07f5b9aa23b577dd5e3de82b71e7d66e148a3888.tar.gz gcc-07f5b9aa23b577dd5e3de82b71e7d66e148a3888.tar.bz2 | |
sh.c (sh_expand_epilogue): Emit a blockage insn before cutting back the stack.
* sh.c (sh_expand_epilogue): Emit a blockage insn before
cutting back the stack.
From-SVN: r14362
| -rw-r--r-- | gcc/config/sh/sh.c | 21 |
1 files changed, 15 insertions, 6 deletions
diff --git a/gcc/config/sh/sh.c b/gcc/config/sh/sh.c index fb723ba5..30406f6 100644 --- a/gcc/config/sh/sh.c +++ b/gcc/config/sh/sh.c @@ -2705,15 +2705,24 @@ sh_expand_epilogue () if (frame_pointer_needed) { - /* We deliberately make the add dependent on the frame_pointer, - to ensure that instruction scheduling won't move the stack pointer - adjust before instructions reading from the frame. This can fail - if there is an interrupt which then writes to the stack. */ output_stack_adjust (get_frame_size (), frame_pointer_rtx, 7); + + /* We must avoid moving the stack pointer adjustment past code + which reads from the local frame, else an interrupt could + occur after the SP adjustment and clobber data in the local + frame. */ + emit_insn (gen_blockage ()); emit_insn (gen_movsi (stack_pointer_rtx, frame_pointer_rtx)); } - else - output_stack_adjust (get_frame_size (), stack_pointer_rtx, 7); + else if (get_frame_size ()) + { + /* We must avoid moving the stack pointer adjustment past code + which reads from the local frame, else an interrupt could + occur after the SP adjustment and clobber data in the local + frame. */ + emit_insn (gen_blockage ()); + output_stack_adjust (get_frame_size (), stack_pointer_rtx, 7); + } /* Pop all the registers. */ |