| Message ID | 561D2085.90802@adacore.com |
|---|---|
| State | New |
| Headers | show |
On 10/13/2015 05:17 PM, Pierre-Marie de Rodat wrote: > The first attached patch is the second attempt to fix PR > rtl-optimization/66790 (see > <https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66790>). > > The second one is a fix for some inconsistency noticed while working on > the original bug. This specific patch fixes no known bug, but anyway… > > Both were bootstrapped and regtested on x86_64-linux. Ok to commit? > Thank you in advance! > > [PATCH 1/2] REE: fix uninitialized registers handling This one is OK with minor changes. I ran some tests with it, and the mir sets look good this time. Code generation still seems unaffected by it on all my example code (which is as expected). > + > + /* Ignoring artificial defs is intentionnal: these often pretend that some "intentional". > + if ((!bitmap_equal_p (&problem_data->in[bb->index], DF_MIR_IN (bb))) > + || (!bitmap_equal_p (&problem_data->out[bb->index], DF_MIR_OUT (bb)))) > + { > + /*df_dump (stderr);*/ > + gcc_unreachable (); > + } Please remove the commented out code and then also the unnecessary braces. In general we avoid commented out code in gcc, but when doing it, #if 0 is generally a better method. > + const rtx reg = XEXP (src, 0); Drop the const maybe? It doesn't seem to add much and the idiom is to just use rtx. >>From ff694bf70e0b1ebd336c684713ce6153cc26b3d6 Mon Sep 17 00:00:00 2001 > From: Pierre-Marie de Rodat<derodat@adacore.com> > Date: Tue, 22 Sep 2015 16:02:41 +0200 > Subject: [PATCH 2/2] DF_LIVE: make clobbers cancel effect of previous GENs in > the same BBs > > gcc/ChangeLog: > > * df-problems.c (df_live_bb_local_compute): Clear GEN bits for > DF_REF_MUST_CLOBBER references. This one is probably ok too; I still want to experiment with it a little. Bernd
On 10/13/2015 05:17 PM, Pierre-Marie de Rodat wrote: > diff --git a/gcc/df-problems.c b/gcc/df-problems.c > index c08ae36..56e1cf5 100644 > --- a/gcc/df-problems.c > +++ b/gcc/df-problems.c > @@ -1464,9 +1464,12 @@ df_live_bb_local_compute (unsigned int bb_index) > seen are included in the gen set. */ > bitmap_set_bit (&bb_info->gen, regno); > else if (DF_REF_FLAGS_IS_SET (def, DF_REF_MUST_CLOBBER)) > - /* Only must clobbers for the entire reg destroy the > - value. */ > - bitmap_set_bit (&bb_info->kill, regno); > + { > + /* Only must clobbers for the entire reg destroy the > + value. */ > + bitmap_set_bit (&bb_info->kill, regno); > + bitmap_clear_bit (&bb_info->gen, regno); > + } > else if (! DF_REF_FLAGS_IS_SET (def, DF_REF_MAY_CLOBBER)) > bitmap_set_bit (&bb_info->gen, regno); > } I think I haven't approved that yet. It is ok, but I do wonder whether there really is a point distinguishing between MUST_CLOBBER and MAY_CLOBBER. Bernd
From ff694bf70e0b1ebd336c684713ce6153cc26b3d6 Mon Sep 17 00:00:00 2001 From: Pierre-Marie de Rodat <derodat@adacore.com> Date: Tue, 22 Sep 2015 16:02:41 +0200 Subject: [PATCH 2/2] DF_LIVE: make clobbers cancel effect of previous GENs in the same BBs gcc/ChangeLog: * df-problems.c (df_live_bb_local_compute): Clear GEN bits for DF_REF_MUST_CLOBBER references. --- gcc/df-problems.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/gcc/df-problems.c b/gcc/df-problems.c index c08ae36..56e1cf5 100644 --- a/gcc/df-problems.c +++ b/gcc/df-problems.c @@ -1464,9 +1464,12 @@ df_live_bb_local_compute (unsigned int bb_index) seen are included in the gen set. */ bitmap_set_bit (&bb_info->gen, regno); else if (DF_REF_FLAGS_IS_SET (def, DF_REF_MUST_CLOBBER)) - /* Only must clobbers for the entire reg destroy the - value. */ - bitmap_set_bit (&bb_info->kill, regno); + { + /* Only must clobbers for the entire reg destroy the + value. */ + bitmap_set_bit (&bb_info->kill, regno); + bitmap_clear_bit (&bb_info->gen, regno); + } else if (! DF_REF_FLAGS_IS_SET (def, DF_REF_MAY_CLOBBER)) bitmap_set_bit (&bb_info->gen, regno); } -- 2.6.0
Hello, The first attached patch is the second attempt to fix PR rtl-optimization/66790 (see <https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66790>). The second one is a fix for some inconsistency noticed while working on the original bug. This specific patch fixes no known bug, but anyway… Both were bootstrapped and regtested on x86_64-linux. Ok to commit? Thank you in advance! [PATCH 1/2] REE: fix uninitialized registers handling gcc/ChangeLog: PR rtl-optimization/66790 * df.h (DF_MIR): New macro. (DF_LAST_PROBLEM_PLUS1): Update to be past DF_MIR (DF_MIR_INFO_BB): New macro. (DF_MIR_IN, DF_MIR_OUT): New macros. (struct df_mir_bb_info): New. (df_mir): New macro. (df_mir_add_problem, df_mir_simulate_one_insn): New forward declarations. (df_mir_get_bb_info): New. * df-problems.c (struct df_mir_problem_data): New. (df_mir_free_bb_info, df_mir_alloc, df_mir_reset, df_mir_bb_local_compute, df_mir_local_compute, df_mir_init, df_mir_confluence_0, df_mir_confluence_n, df_mir_transfer_function, df_mir_free, df_mir_top_dump, df_mir_bottom_dump, df_mir_verify_solution_start, df_mir_verify_solution_end): New. (problem_MIR): New. (df_mir_add_problem, df_mir_simulate_one_insn): New. * timevar.def (TV_DF_MIR): New. * ree.c: Include bitmap.h (add_removable_extension): Add an INIT_REGS parameter. Use it to skip zero-extensions that may get an uninitialized register. (find_removable_extensions): Compute must-initialized registers using the MIR dataflow problem. Update the call to add_removable_extension. (find_and_remove_re): Call df_mir_add_problem. gcc/testsuite/ChangeLog: * gnat.dg/opt50.adb: New test. * gnat.dg/opt50_pkg.adb: New helper. * gnat.dg/opt50_pkg.ads: New helper. [PATCH 2/2] DF_LIVE: make clobbers cancel effect of previous GENs in the same BBs gcc/ChangeLog: * df-problems.c (df_live_bb_local_compute): Clear GEN bits for DF_REF_MUST_CLOBBER references.