Message ID | CABu31nPKUkhm3BprYx=V_TQCjLwRg9RwaT1O89e6FJM3GBNu8A@mail.gmail.com |
---|---|
State | New |
Headers | show |
On Mon, Mar 11, 2013 at 12:17 AM, Steven Bosscher <stevenb.gcc@gmail.com> wrote: > Hello, > > RTL PRE has an option to disable load motion. This option works fine, > except that all analysis for load motion is still performed. > > This patch stops gcse.c from recording memory sets for -fno-gcse-lm, > and conservatively returns true in oprs_unchanged_p for any MEM. > > Bootstrapped&tested on {x86_64,powerpc64}-unknown-linux-gnu. OK? Ok. Thanks, Richard. > Ciao! > Steven > > > * gcse.c (oprs_unchanged_p): Respect flag_gcse_lm. > (record_last_mem_set_info): Likewise. > > Index: gcse.c > =================================================================== > --- gcse.c (revision 196576) > +++ gcse.c (working copy) > @@ -890,8 +890,9 @@ oprs_unchanged_p (const_rtx x, const_rtx > } > > case MEM: > - if (load_killed_in_block_p (current_bb, DF_INSN_LUID (insn), > - x, avail_p)) > + if (! flag_gcse_lm > + || load_killed_in_block_p (current_bb, DF_INSN_LUID (insn), > + x, avail_p)) > return 0; > else > return oprs_unchanged_p (XEXP (x, 0), insn, avail_p); > @@ -1471,10 +1472,14 @@ canon_list_insert (rtx dest ATTRIBUTE_UN > static void > record_last_mem_set_info (rtx insn) > { > - int bb = BLOCK_FOR_INSN (insn)->index; > + int bb; > + > + if (! flag_gcse_lm) > + return; > > /* load_killed_in_block_p will handle the case of calls clobbering > everything. */ > + bb = BLOCK_FOR_INSN (insn)->index; > modify_mem_list[bb].safe_push (insn); > bitmap_set_bit (modify_mem_list_set, bb);
Index: gcse.c =================================================================== --- gcse.c (revision 196576) +++ gcse.c (working copy) @@ -890,8 +890,9 @@ oprs_unchanged_p (const_rtx x, const_rtx } case MEM: - if (load_killed_in_block_p (current_bb, DF_INSN_LUID (insn), - x, avail_p)) + if (! flag_gcse_lm + || load_killed_in_block_p (current_bb, DF_INSN_LUID (insn), + x, avail_p)) return 0; else return oprs_unchanged_p (XEXP (x, 0), insn, avail_p); @@ -1471,10 +1472,14 @@ canon_list_insert (rtx dest ATTRIBUTE_UN static void record_last_mem_set_info (rtx insn) { - int bb = BLOCK_FOR_INSN (insn)->index; + int bb; + + if (! flag_gcse_lm) + return; /* load_killed_in_block_p will handle the case of calls clobbering everything. */ + bb = BLOCK_FOR_INSN (insn)->index; modify_mem_list[bb].safe_push (insn); bitmap_set_bit (modify_mem_list_set, bb);