From 2a2e6784074e1f7b679bc09b1a66982bf60645a5 Mon Sep 17 00:00:00 2001 From: Andrew Pinski Date: Mon, 28 Oct 2024 16:40:34 -0700 Subject: [PATCH] ifcombine: For short circuit case, allow 2 convert defining statements [PR85605] r0-126134-g5d2a9da9a7f7c1 added support for circuiting and combing the ifs into using either AND or OR. But it only allowed the inner condition basic block having the conditional only. This changes to allow up to 2 defining statements as long as they are just integer to integer conversions for either the lhs or rhs of the conditional. This should allow to use ccmp on aarch64 and x86_64 (APX) slightly more than before. Boootstrapped and tested on x86_64-linux-gnu. PR tree-optimization/85605 gcc/ChangeLog: * tree-ssa-ifcombine.cc (can_combine_bbs_with_short_circuit): New function. (ifcombine_ifandif): Use can_combine_bbs_with_short_circuit instead of checking if iterator is one before the last statement. gcc/testsuite/ChangeLog: * g++.dg/tree-ssa/ifcombine-ccmp-1.C: New test. * gcc.dg/tree-ssa/ssa-ifcombine-ccmp-7.c: New test. * gcc.dg/tree-ssa/ssa-ifcombine-ccmp-8.c: New test. * gcc.dg/tree-ssa/ssa-ifcombine-ccmp-9.c: New test. Signed-off-by: Andrew Pinski --- .../g++.dg/tree-ssa/ifcombine-ccmp-1.C | 27 ++++++++++++++ .../gcc.dg/tree-ssa/ssa-ifcombine-ccmp-7.c | 18 +++++++++ .../gcc.dg/tree-ssa/ssa-ifcombine-ccmp-8.c | 19 ++++++++++ .../gcc.dg/tree-ssa/ssa-ifcombine-ccmp-9.c | 17 +++++++++ gcc/tree-ssa-ifcombine.cc | 37 ++++++++++++++++++- 5 files changed, 116 insertions(+), 2 deletions(-) create mode 100644 gcc/testsuite/g++.dg/tree-ssa/ifcombine-ccmp-1.C create mode 100644 gcc/testsuite/gcc.dg/tree-ssa/ssa-ifcombine-ccmp-7.c create mode 100644 gcc/testsuite/gcc.dg/tree-ssa/ssa-ifcombine-ccmp-8.c create mode 100644 gcc/testsuite/gcc.dg/tree-ssa/ssa-ifcombine-ccmp-9.c diff --git a/gcc/testsuite/g++.dg/tree-ssa/ifcombine-ccmp-1.C b/gcc/testsuite/g++.dg/tree-ssa/ifcombine-ccmp-1.C new file mode 100644 index 00000000000..282cec8c628 --- /dev/null +++ b/gcc/testsuite/g++.dg/tree-ssa/ifcombine-ccmp-1.C @@ -0,0 +1,27 @@ +/* { dg-do compile } */ +/* { dg-options "-O2 -g -fdump-tree-optimized --param logical-op-non-short-circuit=1" } */ + +/* PR tree-optimization/85605 */ +#include + +template +inline bool cmp(T a, T2 b) { + return a<0 ? true : T2(a) < b; +} + +template +inline bool cmp2(T a, T2 b) { + return (a<0) | (T2(a) < b); +} + +bool f(int a, int b) { + return cmp(int64_t(a), unsigned(b)); +} + +bool f2(int a, int b) { + return cmp2(int64_t(a), unsigned(b)); +} + + +/* Both of these functions should be optimized to the same, and have an | in them. */ +/* { dg-final { scan-tree-dump-times " \\\| " 2 "optimized" } } */ diff --git a/gcc/testsuite/gcc.dg/tree-ssa/ssa-ifcombine-ccmp-7.c b/gcc/testsuite/gcc.dg/tree-ssa/ssa-ifcombine-ccmp-7.c new file mode 100644 index 00000000000..1bdbb9358b4 --- /dev/null +++ b/gcc/testsuite/gcc.dg/tree-ssa/ssa-ifcombine-ccmp-7.c @@ -0,0 +1,18 @@ +/* { dg-do compile } */ +/* { dg-options "-O2 -g -fdump-tree-optimized --param logical-op-non-short-circuit=1" } */ + +/* PR tree-optimization/85605 */ +/* Like ssa-ifcombine-ccmp-1.c but with conversion from unsigned to signed in the + inner bb which should be able to move too. */ + +int t (int a, unsigned b) +{ + if (a > 0) + { + signed t = b; + if (t > 0) + return 0; + } + return 1; +} +/* { dg-final { scan-tree-dump "\&" "optimized" } } */ diff --git a/gcc/testsuite/gcc.dg/tree-ssa/ssa-ifcombine-ccmp-8.c b/gcc/testsuite/gcc.dg/tree-ssa/ssa-ifcombine-ccmp-8.c new file mode 100644 index 00000000000..8d74b4932c5 --- /dev/null +++ b/gcc/testsuite/gcc.dg/tree-ssa/ssa-ifcombine-ccmp-8.c @@ -0,0 +1,19 @@ +/* { dg-do compile } */ +/* { dg-options "-O2 -g -fdump-tree-optimized --param logical-op-non-short-circuit=1" } */ + +/* PR tree-optimization/85605 */ +/* Like ssa-ifcombine-ccmp-2.c but with conversion from unsigned to signed in the + inner bb which should be able to move too. */ + +int t (int a, unsigned b) +{ + if (a > 0) + goto L1; + signed t = b; + if (t > 0) + goto L1; + return 0; +L1: + return 1; +} +/* { dg-final { scan-tree-dump "\|" "optimized" } } */ diff --git a/gcc/testsuite/gcc.dg/tree-ssa/ssa-ifcombine-ccmp-9.c b/gcc/testsuite/gcc.dg/tree-ssa/ssa-ifcombine-ccmp-9.c new file mode 100644 index 00000000000..4e8350fad41 --- /dev/null +++ b/gcc/testsuite/gcc.dg/tree-ssa/ssa-ifcombine-ccmp-9.c @@ -0,0 +1,17 @@ +/* { dg-do compile } */ +/* { dg-options "-O2 -g -fdump-tree-optimized --param logical-op-non-short-circuit=1" } */ + +/* PR tree-optimization/85605 */ +/* Like ssa-ifcombine-ccmp-1.c but with conversion from short to int in the + inner bb which should be able to move too. */ + +int t (int a, short b, int c) +{ + if (a > 0) + { + if (c == b) + return 0; + } + return 1; +} +/* { dg-final { scan-tree-dump "\&" "optimized" } } */ diff --git a/gcc/tree-ssa-ifcombine.cc b/gcc/tree-ssa-ifcombine.cc index b87ed1189df..9b9dc10cd22 100644 --- a/gcc/tree-ssa-ifcombine.cc +++ b/gcc/tree-ssa-ifcombine.cc @@ -776,6 +776,36 @@ ifcombine_replace_cond (gcond *inner_cond, bool inner_inv, return true; } +/* Returns true if inner_cond_bb contains just the condition or 1/2 statements + that define lhs or rhs with an integer conversion. */ + +static bool +can_combine_bbs_with_short_circuit (basic_block inner_cond_bb, tree lhs, tree rhs) +{ + gimple_stmt_iterator gsi; + gsi = gsi_start_nondebug_after_labels_bb (inner_cond_bb); + /* If only the condition, this should be allowed. */ + if (gsi_one_before_end_p (gsi)) + return true; + /* Can have up to 2 statements defining each of lhs/rhs. */ + for (int i = 0; i < 2; i++) + { + gimple *stmt = gsi_stmt (gsi); + if (!is_gimple_assign (stmt) + || !CONVERT_EXPR_CODE_P (gimple_assign_rhs_code (stmt))) + return false; + /* The defining statement needs to match either the lhs or rhs of + the condition. */ + if (lhs != gimple_assign_lhs (stmt) + && rhs != gimple_assign_lhs (stmt)) + return false; + gsi_next_nondebug (&gsi); + if (gsi_one_before_end_p (gsi)) + return true; + } + return false; +} + /* If-convert on a and pattern with a common else block. The inner if is specified by its INNER_COND_BB, the outer by OUTER_COND_BB. inner_inv, outer_inv indicate whether the conditions are inverted. @@ -951,8 +981,11 @@ ifcombine_ifandif (basic_block inner_cond_bb, bool inner_inv, = param_logical_op_non_short_circuit; if (!logical_op_non_short_circuit || sanitize_coverage_p ()) return false; - /* Only do this optimization if the inner bb contains only the conditional. */ - if (!gsi_one_before_end_p (gsi_start_nondebug_after_labels_bb (inner_cond_bb))) + /* Only do this optimization if the inner bb contains only the conditional + or there is one or 2 statements which are nop conversion for the comparison. */ + if (!can_combine_bbs_with_short_circuit (inner_cond_bb, + gimple_cond_lhs (inner_cond), + gimple_cond_rhs (inner_cond))) return false; t1 = fold_build2_loc (gimple_location (inner_cond), inner_cond_code,