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| author | Kaveh R. Ghazi <ghazi@caip.rutgers.edu> | 2007-02-03 16:13:23 +0000 |
|---|---|---|
| committer | Kaveh Ghazi <ghazi@gcc.gnu.org> | 2007-02-03 16:13:23 +0000 |
| commit | d1ad84c20452e63a38a6b414a6eb7001711c520a (patch) | |
| tree | 6f5c23e0e626e6b83e80b93c1170d1bf55370b71 /gcc/builtins.c | |
| parent | 36f7dcae093c3ed596010a4bf88ce731a7d6236e (diff) | |
| download | gcc-d1ad84c20452e63a38a6b414a6eb7001711c520a.zip gcc-d1ad84c20452e63a38a6b414a6eb7001711c520a.tar.gz gcc-d1ad84c20452e63a38a6b414a6eb7001711c520a.tar.bz2 | |
builtins.c (fold_builtin_cabs): Fold cabs(x+xi) into fabs(x)*sqrt(2).
* builtins.c (fold_builtin_cabs): Fold cabs(x+xi) into
fabs(x)*sqrt(2).
* fold-const.c (fold_binary): Fix comment typos. Fold complex
(x,0)-(0,y) into (x,-y). Likewise (0,y)-(x,0) into (-x,y).
testsuite:
* gcc.dg/builtins-54.c: Add more cases.
From-SVN: r121542
Diffstat (limited to 'gcc/builtins.c')
| -rw-r--r-- | gcc/builtins.c | 31 |
1 files changed, 24 insertions, 7 deletions
diff --git a/gcc/builtins.c b/gcc/builtins.c index 5b9a87f..b7ce1e4 100644 --- a/gcc/builtins.c +++ b/gcc/builtins.c @@ -7143,13 +7143,30 @@ fold_builtin_cabs (tree arglist, tree type, tree fndecl) type, mpfr_hypot))) return res; - /* If either part is zero, cabs is fabs of the other. */ - if (TREE_CODE (arg) == COMPLEX_EXPR - && real_zerop (TREE_OPERAND (arg, 0))) - return fold_build1 (ABS_EXPR, type, TREE_OPERAND (arg, 1)); - if (TREE_CODE (arg) == COMPLEX_EXPR - && real_zerop (TREE_OPERAND (arg, 1))) - return fold_build1 (ABS_EXPR, type, TREE_OPERAND (arg, 0)); + if (TREE_CODE (arg) == COMPLEX_EXPR) + { + tree real = TREE_OPERAND (arg, 0); + tree imag = TREE_OPERAND (arg, 1); + + /* If either part is zero, cabs is fabs of the other. */ + if (real_zerop (real)) + return fold_build1 (ABS_EXPR, type, imag); + if (real_zerop (imag)) + return fold_build1 (ABS_EXPR, type, real); + + /* cabs(x+xi) -> fabs(x)*sqrt(2). */ + if (flag_unsafe_math_optimizations + && operand_equal_p (real, imag, OEP_PURE_SAME)) + { + REAL_VALUE_TYPE sqrt2; + + real_sqrt (&sqrt2, TYPE_MODE (type), &dconst2); + STRIP_NOPS (real); + return fold_build2 (MULT_EXPR, type, + fold_build1 (ABS_EXPR, type, real), + build_real (type, sqrt2)); + } + } /* Optimize cabs(-z) and cabs(conj(z)) as cabs(z). */ if (TREE_CODE (arg) == NEGATE_EXPR |