| Message ID | 20101216214916.GA2198@tyan-ft48-01.lab.bos.redhat.com |
|---|---|
| State | New |
| Headers | show |
On Thu, Dec 16, 2010 at 10:49 PM, Jakub Jelinek <jakub@redhat.com> wrote: > Hi! > > The reduction_list hash table in parloops is hashed using htab_hash_pointer > on the gimple stmt and later on htab_traversed with code generation in the > callback, which not only can cause code differences with -g/-g0, but also > with AS randomization could result in different generated code. > > Unfortunately, the pass changes the result SSA_NAME of the PHI, so we > can't use its SSA_NAME_VERSION all the time as the hash value, and during > gather_scalar_reductions we can't use gimple_uid, as it is used by the > vectorizer. So, this patch starts using SSA_NAME_VERSION, at the end > of gather_scalar_reductions sets gimple_uid of the PHIs to the corresponding > SSA_NAME_VERSION and afterwards in reduction_phi uses gimple_uid. > > Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk? Ok. Thanks, Richard. > 2010-12-16 Jakub Jelinek <jakub@redhat.com> > > PR tree-optimization/46969 > * tree-parloops.c (struct reduction_info): Add reduc_version. > (reduction_info_hash): Return reduc_version field. > (reduction_phi): Set reduc_version to gimple_uid (phi). > (build_new_reduction): Set reduc_version to SSA_NAME_VERSION of > phi result. > (set_reduc_phi_uids): New function. > (gather_scalar_reductions): Call it at the end through htab_traverse. > > * gcc.dg/autopar/pr46969.c: New test. > > --- gcc/tree-parloops.c.jj 2010-12-07 17:32:49.000000000 +0100 > +++ gcc/tree-parloops.c 2010-12-16 13:45:57.000000000 +0100 > @@ -168,6 +168,8 @@ struct reduction_info > gimple reduc_stmt; /* reduction statement. */ > gimple reduc_phi; /* The phi node defining the reduction. */ > enum tree_code reduction_code;/* code for the reduction operation. */ > + unsigned reduc_version; /* SSA_NAME_VERSION of original reduc_phi > + result. */ > gimple keep_res; /* The PHI_RESULT of this phi is the resulting value > of the reduction variable when existing the loop. */ > tree initial_value; /* The initial value of the reduction var before entering the loop. */ > @@ -195,7 +197,7 @@ reduction_info_hash (const void *aa) > { > const struct reduction_info *a = (const struct reduction_info *) aa; > > - return htab_hash_pointer (a->reduc_phi); > + return a->reduc_version; > } > > static struct reduction_info * > @@ -207,6 +209,7 @@ reduction_phi (htab_t reduction_list, gi > return NULL; > > tmpred.reduc_phi = phi; > + tmpred.reduc_version = gimple_uid (phi); > red = (struct reduction_info *) htab_find (reduction_list, &tmpred); > > return red; > @@ -1774,11 +1777,22 @@ build_new_reduction (htab_t reduction_li > > new_reduction->reduc_stmt = reduc_stmt; > new_reduction->reduc_phi = phi; > + new_reduction->reduc_version = SSA_NAME_VERSION (gimple_phi_result (phi)); > new_reduction->reduction_code = gimple_assign_rhs_code (reduc_stmt); > slot = htab_find_slot (reduction_list, new_reduction, INSERT); > *slot = new_reduction; > } > > +/* Callback for htab_traverse. Sets gimple_uid of reduc_phi stmts. */ > + > +static int > +set_reduc_phi_uids (void **slot, void *data ATTRIBUTE_UNUSED) > +{ > + struct reduction_info *const red = (struct reduction_info *) *slot; > + gimple_set_uid (red->reduc_phi, red->reduc_version); > + return 1; > +} > + > /* Detect all reductions in the LOOP, insert them into REDUCTION_LIST. */ > > static void > @@ -1810,7 +1824,12 @@ gather_scalar_reductions (loop_p loop, h > build_new_reduction (reduction_list, reduc_stmt, phi); > } > } > - destroy_loop_vec_info (simple_loop_info, true); > + destroy_loop_vec_info (simple_loop_info, true); > + > + /* As gimple_uid is used by the vectorizer in between vect_analyze_loop_form > + and destroy_loop_vec_info, we can set gimple_uid of reduc_phi stmts > + only now. */ > + htab_traverse (reduction_list, set_reduc_phi_uids, NULL); > } > > /* Try to initialize NITER for code generation part. */ > --- gcc/testsuite/gcc.dg/autopar/pr46969.c.jj 2010-12-16 14:06:42.000000000 +0100 > +++ gcc/testsuite/gcc.dg/autopar/pr46969.c 2010-12-16 14:05:42.000000000 +0100 > @@ -0,0 +1,31 @@ > +/* PR tree-optimization/46969 */ > +/* { dg-do compile } */ > +/* { dg-options "-O3 -ftree-parallelize-loops=2 -fcompare-debug" } */ > + > +extern void abort (void); > +#define F(name) \ > +int \ > +name (unsigned char *x) \ > +{ \ > + int i; \ > + unsigned int c, d, e; \ > + if (x != 0) \ > + { \ > + for (i = 0, d = 0, e = 0xFFFFFFFF; \ > + i < 64; \ > + i += (int) sizeof(unsigned int)) \ > + { \ > + c = *((unsigned int *)(&x[i])); \ > + d = d | c; \ > + e = e & c; \ > + } \ > + if (!((d == e) && ((d >> 8) == (e & 0x00FFFFFF)))) \ > + abort (); \ > + } \ > + return 0; \ > +} > +F (foo0) F (foo1) > +F (foo2) F (foo3) > +F (foo4) F (foo5) > +F (foo6) F (foo7) > +F (foo8) F (foo9) > > Jakub >
--- gcc/tree-parloops.c.jj 2010-12-07 17:32:49.000000000 +0100 +++ gcc/tree-parloops.c 2010-12-16 13:45:57.000000000 +0100 @@ -168,6 +168,8 @@ struct reduction_info gimple reduc_stmt; /* reduction statement. */ gimple reduc_phi; /* The phi node defining the reduction. */ enum tree_code reduction_code;/* code for the reduction operation. */ + unsigned reduc_version; /* SSA_NAME_VERSION of original reduc_phi + result. */ gimple keep_res; /* The PHI_RESULT of this phi is the resulting value of the reduction variable when existing the loop. */ tree initial_value; /* The initial value of the reduction var before entering the loop. */ @@ -195,7 +197,7 @@ reduction_info_hash (const void *aa) { const struct reduction_info *a = (const struct reduction_info *) aa; - return htab_hash_pointer (a->reduc_phi); + return a->reduc_version; } static struct reduction_info * @@ -207,6 +209,7 @@ reduction_phi (htab_t reduction_list, gi return NULL; tmpred.reduc_phi = phi; + tmpred.reduc_version = gimple_uid (phi); red = (struct reduction_info *) htab_find (reduction_list, &tmpred); return red; @@ -1774,11 +1777,22 @@ build_new_reduction (htab_t reduction_li new_reduction->reduc_stmt = reduc_stmt; new_reduction->reduc_phi = phi; + new_reduction->reduc_version = SSA_NAME_VERSION (gimple_phi_result (phi)); new_reduction->reduction_code = gimple_assign_rhs_code (reduc_stmt); slot = htab_find_slot (reduction_list, new_reduction, INSERT); *slot = new_reduction; } +/* Callback for htab_traverse. Sets gimple_uid of reduc_phi stmts. */ + +static int +set_reduc_phi_uids (void **slot, void *data ATTRIBUTE_UNUSED) +{ + struct reduction_info *const red = (struct reduction_info *) *slot; + gimple_set_uid (red->reduc_phi, red->reduc_version); + return 1; +} + /* Detect all reductions in the LOOP, insert them into REDUCTION_LIST. */ static void @@ -1810,7 +1824,12 @@ gather_scalar_reductions (loop_p loop, h build_new_reduction (reduction_list, reduc_stmt, phi); } } - destroy_loop_vec_info (simple_loop_info, true); + destroy_loop_vec_info (simple_loop_info, true); + + /* As gimple_uid is used by the vectorizer in between vect_analyze_loop_form + and destroy_loop_vec_info, we can set gimple_uid of reduc_phi stmts + only now. */ + htab_traverse (reduction_list, set_reduc_phi_uids, NULL); } /* Try to initialize NITER for code generation part. */ --- gcc/testsuite/gcc.dg/autopar/pr46969.c.jj 2010-12-16 14:06:42.000000000 +0100 +++ gcc/testsuite/gcc.dg/autopar/pr46969.c 2010-12-16 14:05:42.000000000 +0100 @@ -0,0 +1,31 @@ +/* PR tree-optimization/46969 */ +/* { dg-do compile } */ +/* { dg-options "-O3 -ftree-parallelize-loops=2 -fcompare-debug" } */ + +extern void abort (void); +#define F(name) \ +int \ +name (unsigned char *x) \ +{ \ + int i; \ + unsigned int c, d, e; \ + if (x != 0) \ + { \ + for (i = 0, d = 0, e = 0xFFFFFFFF; \ + i < 64; \ + i += (int) sizeof(unsigned int)) \ + { \ + c = *((unsigned int *)(&x[i])); \ + d = d | c; \ + e = e & c; \ + } \ + if (!((d == e) && ((d >> 8) == (e & 0x00FFFFFF)))) \ + abort (); \ + } \ + return 0; \ +} +F (foo0) F (foo1) +F (foo2) F (foo3) +F (foo4) F (foo5) +F (foo6) F (foo7) +F (foo8) F (foo9)