diff options
Diffstat (limited to 'gcc/fold-const.c')
| -rw-r--r-- | gcc/fold-const.c | 41 |
1 files changed, 39 insertions, 2 deletions
diff --git a/gcc/fold-const.c b/gcc/fold-const.c index 241e9dc..085fcd8 100644 --- a/gcc/fold-const.c +++ b/gcc/fold-const.c @@ -8923,7 +8923,7 @@ fold_binary (enum tree_code code, tree type, tree op0, tree op1) /* Fold __complex__ ( x, 0 ) + __complex__ ( 0, y ) to __complex__ ( x, y ). This is not the same for SNaNs or - if singed zeros are involved. */ + if signed zeros are involved. */ if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0))) && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0))) && COMPLEX_FLOAT_TYPE_P (TREE_TYPE (arg0))) @@ -9231,6 +9231,43 @@ fold_binary (enum tree_code code, tree type, tree op0, tree op1) else if (fold_real_zero_addition_p (TREE_TYPE (arg1), arg0, 0)) return negate_expr (fold_convert (type, arg1)); + /* Fold __complex__ ( x, 0 ) - __complex__ ( 0, y ) to + __complex__ ( x, -y ). This is not the same for SNaNs or if + signed zeros are involved. */ + if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0))) + && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0))) + && COMPLEX_FLOAT_TYPE_P (TREE_TYPE (arg0))) + { + tree rtype = TREE_TYPE (TREE_TYPE (arg0)); + tree arg0r = fold_unary (REALPART_EXPR, rtype, arg0); + tree arg0i = fold_unary (IMAGPART_EXPR, rtype, arg0); + bool arg0rz = false, arg0iz = false; + if ((arg0r && (arg0rz = real_zerop (arg0r))) + || (arg0i && (arg0iz = real_zerop (arg0i)))) + { + tree arg1r = fold_unary (REALPART_EXPR, rtype, arg1); + tree arg1i = fold_unary (IMAGPART_EXPR, rtype, arg1); + if (arg0rz && arg1i && real_zerop (arg1i)) + { + tree rp = fold_build1 (NEGATE_EXPR, rtype, + arg1r ? arg1r + : build1 (REALPART_EXPR, rtype, arg1)); + tree ip = arg0i ? arg0i + : build1 (IMAGPART_EXPR, rtype, arg0); + return fold_build2 (COMPLEX_EXPR, type, rp, ip); + } + else if (arg0iz && arg1r && real_zerop (arg1r)) + { + tree rp = arg0r ? arg0r + : build1 (REALPART_EXPR, rtype, arg0); + tree ip = fold_build1 (NEGATE_EXPR, rtype, + arg1i ? arg1i + : build1 (IMAGPART_EXPR, rtype, arg1)); + return fold_build2 (COMPLEX_EXPR, type, rp, ip); + } + } + } + /* Fold &x - &x. This can happen from &x.foo - &x. This is unsafe for certain floats even in non-IEEE formats. In IEEE, it is unsafe because it does wrong for NaNs. @@ -9410,7 +9447,7 @@ fold_binary (enum tree_code code, tree type, tree op0, tree op1) } /* Fold z * +-I to __complex__ (-+__imag z, +-__real z). - This is not the same for NaNs or if singed zeros are + This is not the same for NaNs or if signed zeros are involved. */ if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0))) && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0))) |