diff options
Diffstat (limited to 'gcc/fold-const.c')
| -rw-r--r-- | gcc/fold-const.c | 69 |
1 files changed, 56 insertions, 13 deletions
diff --git a/gcc/fold-const.c b/gcc/fold-const.c index 8aceb73..fa75fdb 100644 --- a/gcc/fold-const.c +++ b/gcc/fold-const.c @@ -9693,6 +9693,48 @@ fold_addr_of_array_ref_difference (location_t loc, tree type, return NULL_TREE; } +/* If the real or vector real constant CST of type TYPE has an exact + inverse, return it, else return NULL. */ + +static tree +exact_inverse (tree type, tree cst) +{ + REAL_VALUE_TYPE r; + tree unit_type, *elts; + enum machine_mode mode; + unsigned vec_nelts, i; + + switch (TREE_CODE (cst)) + { + case REAL_CST: + r = TREE_REAL_CST (cst); + + if (exact_real_inverse (TYPE_MODE (type), &r)) + return build_real (type, r); + + return NULL_TREE; + + case VECTOR_CST: + vec_nelts = VECTOR_CST_NELTS (cst); + elts = XALLOCAVEC (tree, vec_nelts); + unit_type = TREE_TYPE (type); + mode = TYPE_MODE (unit_type); + + for (i = 0; i < vec_nelts; i++) + { + r = TREE_REAL_CST (VECTOR_CST_ELT (cst, i)); + if (!exact_real_inverse (mode, &r)) + return NULL_TREE; + elts[i] = build_real (unit_type, r); + } + + return build_vector (type, elts); + + default: + return NULL_TREE; + } +} + /* Fold a binary expression of code CODE and type TYPE with operands OP0 and OP1. LOC is the location of the resulting expression. Return the folded expression if folding is successful. Otherwise, @@ -11734,23 +11776,24 @@ fold_binary_loc (location_t loc, so only do this if -freciprocal-math. We can actually always safely do it if ARG1 is a power of two, but it's hard to tell if it is or not in a portable manner. */ - if (TREE_CODE (arg1) == REAL_CST) + if (optimize + && (TREE_CODE (arg1) == REAL_CST + || (TREE_CODE (arg1) == COMPLEX_CST + && COMPLEX_FLOAT_TYPE_P (TREE_TYPE (arg1))) + || (TREE_CODE (arg1) == VECTOR_CST + && VECTOR_FLOAT_TYPE_P (TREE_TYPE (arg1))))) { if (flag_reciprocal_math - && 0 != (tem = const_binop (code, build_real (type, dconst1), - arg1))) + && 0 != (tem = const_binop (code, build_one_cst (type), arg1))) return fold_build2_loc (loc, MULT_EXPR, type, arg0, tem); - /* Find the reciprocal if optimizing and the result is exact. */ - if (optimize) + /* Find the reciprocal if optimizing and the result is exact. + TODO: Complex reciprocal not implemented. */ + if (TREE_CODE (arg1) != COMPLEX_CST) { - REAL_VALUE_TYPE r; - r = TREE_REAL_CST (arg1); - if (exact_real_inverse (TYPE_MODE(TREE_TYPE(arg0)), &r)) - { - tem = build_real (type, r); - return fold_build2_loc (loc, MULT_EXPR, type, - fold_convert_loc (loc, type, arg0), tem); - } + tree inverse = exact_inverse (TREE_TYPE (arg0), arg1); + + if (inverse) + return fold_build2_loc (loc, MULT_EXPR, type, arg0, inverse); } } /* Convert A/B/C to A/(B*C). */ |