diff options
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/testsuite/gcc.target/i386/pr90693.c | 29 | ||||
| -rw-r--r-- | gcc/tree-ssa-math-opts.cc | 76 |
2 files changed, 104 insertions, 1 deletions
diff --git a/gcc/testsuite/gcc.target/i386/pr90693.c b/gcc/testsuite/gcc.target/i386/pr90693.c new file mode 100644 index 0000000..1659f26 --- /dev/null +++ b/gcc/testsuite/gcc.target/i386/pr90693.c @@ -0,0 +1,29 @@ +/* PR tree-optimization/90693 */ +/* { dg-do compile } */ +/* { dg-options "-O2 -mno-abm -mno-popcnt -fdump-tree-optimized" } */ +/* { dg-final { scan-tree-dump-not "POPCOUNT \\\(" "optimized" } } */ +/* { dg-final { scan-tree-dump-not "__builtin_popcount(ll)? \\\(" "optimized" } } */ + +int +foo (unsigned int x) +{ + return __builtin_popcount (x) == 1; +} + +int +bar (unsigned int x) +{ + return (x ^ (x - 1)) > x - 1; +} + +int +baz (unsigned long long x) +{ + return __builtin_popcountll (x) == 1; +} + +int +qux (unsigned long long x) +{ + return (x ^ (x - 1)) > x - 1; +} diff --git a/gcc/tree-ssa-math-opts.cc b/gcc/tree-ssa-math-opts.cc index 95eda43..9bfc2d3 100644 --- a/gcc/tree-ssa-math-opts.cc +++ b/gcc/tree-ssa-math-opts.cc @@ -5154,6 +5154,72 @@ match_uaddc_usubc (gimple_stmt_iterator *gsi, gimple *stmt, tree_code code) return true; } +/* Replace .POPCOUNT (x) == 1 or .POPCOUNT (x) != 1 with + (x & (x - 1)) > x - 1 or (x & (x - 1)) <= x - 1 if .POPCOUNT + isn't a direct optab. */ + +static void +match_single_bit_test (gimple_stmt_iterator *gsi, gimple *stmt) +{ + tree clhs, crhs; + enum tree_code code; + if (gimple_code (stmt) == GIMPLE_COND) + { + clhs = gimple_cond_lhs (stmt); + crhs = gimple_cond_rhs (stmt); + code = gimple_cond_code (stmt); + } + else + { + clhs = gimple_assign_rhs1 (stmt); + crhs = gimple_assign_rhs2 (stmt); + code = gimple_assign_rhs_code (stmt); + } + if (code != EQ_EXPR && code != NE_EXPR) + return; + if (TREE_CODE (clhs) != SSA_NAME || !integer_onep (crhs)) + return; + gimple *call = SSA_NAME_DEF_STMT (clhs); + combined_fn cfn = gimple_call_combined_fn (call); + switch (cfn) + { + CASE_CFN_POPCOUNT: + break; + default: + return; + } + if (!has_single_use (clhs)) + return; + tree arg = gimple_call_arg (call, 0); + tree type = TREE_TYPE (arg); + if (!INTEGRAL_TYPE_P (type)) + return; + if (direct_internal_fn_supported_p (IFN_POPCOUNT, type, OPTIMIZE_FOR_BOTH)) + return; + tree argm1 = make_ssa_name (type); + gimple *g = gimple_build_assign (argm1, PLUS_EXPR, arg, + build_int_cst (type, -1)); + gsi_insert_before (gsi, g, GSI_SAME_STMT); + g = gimple_build_assign (make_ssa_name (type), BIT_XOR_EXPR, arg, argm1); + gsi_insert_before (gsi, g, GSI_SAME_STMT); + if (gcond *cond = dyn_cast <gcond *> (stmt)) + { + gimple_cond_set_lhs (cond, gimple_assign_lhs (g)); + gimple_cond_set_rhs (cond, argm1); + gimple_cond_set_code (cond, code == EQ_EXPR ? GT_EXPR : LE_EXPR); + } + else + { + gimple_assign_set_rhs1 (stmt, gimple_assign_lhs (g)); + gimple_assign_set_rhs2 (stmt, argm1); + gimple_assign_set_rhs_code (stmt, code == EQ_EXPR ? GT_EXPR : LE_EXPR); + } + update_stmt (stmt); + gimple_stmt_iterator gsi2 = gsi_for_stmt (call); + gsi_remove (&gsi2, true); + release_defs (call); +} + /* Return true if target has support for divmod. */ static bool @@ -5807,6 +5873,11 @@ math_opts_dom_walker::after_dom_children (basic_block bb) match_uaddc_usubc (&gsi, stmt, code); break; + case EQ_EXPR: + case NE_EXPR: + match_single_bit_test (&gsi, stmt); + break; + default:; } } @@ -5872,7 +5943,10 @@ math_opts_dom_walker::after_dom_children (basic_block bb) } } else if (gimple_code (stmt) == GIMPLE_COND) - optimize_spaceship (as_a <gcond *> (stmt)); + { + match_single_bit_test (&gsi, stmt); + optimize_spaceship (as_a <gcond *> (stmt)); + } gsi_next (&gsi); } if (fma_state.m_deferring_p |