| Message ID | 20130116152733.GH7269@tucnak.redhat.com |
|---|---|
| State | New |
| Headers | show |
Jakub Jelinek wrote: > As discussed in the PR, this patch performs the decrement of countm1 > before the condition, so that the loop can have empty latch block. > The testcase from the PR then can be vectorized. > > Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk? OK from the FE side. [I leave it to you and Richard whether you prefer this version or the Bool version; quoting from this PR: "Not sure if it is better this way, or with doing assignment of the condition result into a bool and using it later (as done in the patch for the other PR)." (Other PR = PR 53957.)] Thanks for the patch! Tobias > 2013-01-16 Jakub Jelinek <jakub@redhat.com> > > PR fortran/52865 > * trans-stmt.c (gfc_trans_do): Put countm1-- before conditional > and use value of countm1 before the decrement in the condition.
On Wed, 16 Jan 2013, Tobias Burnus wrote: > Jakub Jelinek wrote: > > As discussed in the PR, this patch performs the decrement of countm1 > > before the condition, so that the loop can have empty latch block. > > The testcase from the PR then can be vectorized. > > > > Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk? > > OK from the FE side. > > [I leave it to you and Richard whether you prefer this version or the Bool > version; quoting from this PR: "Not sure if it is better this way, or with > doing assignment of the condition result into a bool and using it later (as > done in the patch for the other PR)." (Other PR = PR 53957.)] Jakubs version is better I suppose. Richard.
--- gcc/fortran/trans-stmt.c.jj 2013-01-11 09:02:50.000000000 +0100 +++ gcc/fortran/trans-stmt.c 2013-01-16 12:47:44.191683738 +0100 @@ -1518,8 +1518,9 @@ gfc_trans_simple_do (gfc_code * code, st body; cycle_label: dovar += step - if (countm1 ==0) goto exit_label; + countm1t = countm1; countm1--; + if (countm1t == 0) goto exit_label; } exit_label: @@ -1739,19 +1740,23 @@ gfc_trans_do (gfc_code * code, tree exit if (gfc_option.rtcheck & GFC_RTCHECK_DO) gfc_add_modify_loc (loc, &body, saved_dovar, dovar); - /* End with the loop condition. Loop until countm1 == 0. */ - cond = fold_build2_loc (loc, EQ_EXPR, boolean_type_node, countm1, - build_int_cst (utype, 0)); - tmp = fold_build1_loc (loc, GOTO_EXPR, void_type_node, exit_label); - tmp = fold_build3_loc (loc, COND_EXPR, void_type_node, - cond, tmp, build_empty_stmt (loc)); - gfc_add_expr_to_block (&body, tmp); + /* Initialize countm1t. */ + tree countm1t = gfc_create_var (utype, "countm1t"); + gfc_add_modify_loc (loc, &body, countm1t, countm1); /* Decrement the loop count. */ tmp = fold_build2_loc (loc, MINUS_EXPR, utype, countm1, build_int_cst (utype, 1)); gfc_add_modify_loc (loc, &body, countm1, tmp); + /* End with the loop condition. Loop until countm1t == 0. */ + cond = fold_build2_loc (loc, EQ_EXPR, boolean_type_node, countm1t, + build_int_cst (utype, 0)); + tmp = fold_build1_loc (loc, GOTO_EXPR, void_type_node, exit_label); + tmp = fold_build3_loc (loc, COND_EXPR, void_type_node, + cond, tmp, build_empty_stmt (loc)); + gfc_add_expr_to_block (&body, tmp); + /* End of loop body. */ tmp = gfc_finish_block (&body);