diff options
Diffstat (limited to 'gcc/tree-ssa-phiopt.c')
-rw-r--r-- | gcc/tree-ssa-phiopt.c | 75 |
1 files changed, 64 insertions, 11 deletions
diff --git a/gcc/tree-ssa-phiopt.c b/gcc/tree-ssa-phiopt.c index 8e8a08b..f133659 100644 --- a/gcc/tree-ssa-phiopt.c +++ b/gcc/tree-ssa-phiopt.c @@ -1988,8 +1988,16 @@ spaceship_replacement (basic_block cond_bb, basic_block middle_bb, gcond *cond1 = as_a <gcond *> (last_stmt (cond_bb)); enum tree_code cmp1 = gimple_cond_code (cond1); - if (cmp1 != LT_EXPR && cmp1 != GT_EXPR) - return false; + switch (cmp1) + { + case LT_EXPR: + case LE_EXPR: + case GT_EXPR: + case GE_EXPR: + break; + default: + return false; + } tree lhs1 = gimple_cond_lhs (cond1); tree rhs1 = gimple_cond_rhs (cond1); /* The optimization may be unsafe due to NaNs. */ @@ -2029,7 +2037,42 @@ spaceship_replacement (basic_block cond_bb, basic_block middle_bb, if (lhs2 == lhs1) { if (!operand_equal_p (rhs2, rhs1, 0)) - return false; + { + if ((cmp2 == EQ_EXPR || cmp2 == NE_EXPR) + && TREE_CODE (rhs1) == INTEGER_CST + && TREE_CODE (rhs2) == INTEGER_CST) + { + /* For integers, we can have cond2 x == 5 + and cond1 x < 5, x <= 4, x <= 5, x < 6, + x > 5, x >= 6, x >= 5 or x > 4. */ + if (tree_int_cst_lt (rhs1, rhs2)) + { + if (wi::ne_p (wi::to_wide (rhs1) + 1, wi::to_wide (rhs2))) + return false; + if (cmp1 == LE_EXPR) + cmp1 = LT_EXPR; + else if (cmp1 == GT_EXPR) + cmp1 = GE_EXPR; + else + return false; + } + else + { + gcc_checking_assert (tree_int_cst_lt (rhs2, rhs1)); + if (wi::ne_p (wi::to_wide (rhs2) + 1, wi::to_wide (rhs1))) + return false; + if (cmp1 == LT_EXPR) + cmp1 = LE_EXPR; + else if (cmp1 == GE_EXPR) + cmp1 = GT_EXPR; + else + return false; + } + rhs1 = rhs2; + } + else + return false; + } } else if (lhs2 == rhs1) { @@ -2061,20 +2104,30 @@ spaceship_replacement (basic_block cond_bb, basic_block middle_bb, || absu_hwi (tree_to_shwi (arg0)) != 1 || wi::to_widest (arg0) == wi::to_widest (arg1)) return false; - if (cmp2 != LT_EXPR && cmp2 != GT_EXPR) - return false; + switch (cmp2) + { + case LT_EXPR: + case LE_EXPR: + case GT_EXPR: + case GE_EXPR: + break; + default: + return false; + } /* if (x < y) goto phi_bb; else fallthru; if (x > y) goto phi_bb; else fallthru; bbx:; phi_bb:; is ok, but if x and y are swapped in one of the comparisons, or the comparisons are the same and operands not swapped, - or second goto phi_bb is not the true edge, it is not. */ + or the true and false edges are swapped, it is not. */ if ((lhs2 == lhs1) - ^ (cmp2 == cmp1) - ^ ((e1->flags & EDGE_TRUE_VALUE) != 0)) - return false; - if ((cond2_phi_edge->flags & EDGE_TRUE_VALUE) == 0) + ^ (((cond2_phi_edge->flags + & ((cmp2 == LT_EXPR || cmp2 == LE_EXPR) + ? EDGE_TRUE_VALUE : EDGE_FALSE_VALUE)) != 0) + != ((e1->flags + & ((cmp1 == LT_EXPR || cmp1 == LE_EXPR) + ? EDGE_TRUE_VALUE : EDGE_FALSE_VALUE)) != 0))) return false; if (!single_pred_p (cond2_bb) || !cond_only_block_p (cond2_bb)) return false; @@ -2124,7 +2177,7 @@ spaceship_replacement (basic_block cond_bb, basic_block middle_bb, /* lhs1 one_cmp rhs1 results in phires of 1. */ enum tree_code one_cmp; - if ((cmp1 == LT_EXPR) + if ((cmp1 == LT_EXPR || cmp1 == LE_EXPR) ^ (!integer_onep ((e1->flags & EDGE_TRUE_VALUE) ? arg1 : arg0))) one_cmp = LT_EXPR; else |