diff options
Diffstat (limited to 'gcc/builtins.c')
| -rw-r--r-- | gcc/builtins.c | 106 |
1 files changed, 104 insertions, 2 deletions
diff --git a/gcc/builtins.c b/gcc/builtins.c index 53a1744..b227ffb 100644 --- a/gcc/builtins.c +++ b/gcc/builtins.c @@ -79,6 +79,11 @@ tree built_in_decls[(int) END_BUILTINS]; required to implement the function call in all cases. */ tree implicit_built_in_decls[(int) END_BUILTINS]; +/* Trigonometric and mathematical constants used in builtin folding. */ +static bool builtin_dconsts_init = 0; +static REAL_VALUE_TYPE dconstpi; +static REAL_VALUE_TYPE dconste; + static int get_pointer_alignment PARAMS ((tree, unsigned int)); static tree c_strlen PARAMS ((tree)); static const char *c_getstr PARAMS ((tree)); @@ -171,7 +176,22 @@ static tree fold_trunc_transparent_mathfn PARAMS ((tree)); static bool readonly_data_expr PARAMS ((tree)); static rtx expand_builtin_fabs PARAMS ((tree, rtx, rtx)); static rtx expand_builtin_cabs PARAMS ((tree, rtx)); +static void init_builtin_dconsts PARAMS ((void)); + +/* Initialize mathematical constants for constant folding builtins. + These constants need to be given to atleast 160 bits precision. */ +static void +init_builtin_dconsts () +{ + real_from_string (&dconstpi, + "3.1415926535897932384626433832795028841971693993751058209749445923078"); + real_from_string (&dconste, + "2.7182818284590452353602874713526624977572470936999595749669676277241"); + + builtin_dconsts_init = true; +} + /* Return the alignment in bits of EXP, a pointer valued expression. But don't return more than MAX_ALIGN no matter what. The alignment returned is, by default, the alignment of the thing that @@ -5213,7 +5233,7 @@ fold_builtin (exp) /* Optimize sin(0.0) = 0.0. */ if (real_zerop (arg)) - return build_real (type, dconst0); + return arg; } break; @@ -5242,6 +5262,41 @@ fold_builtin (exp) if (real_zerop (arg)) return build_real (type, dconst1); + /* Optimize exp(1.0) = e. */ + if (real_onep (arg)) + { + REAL_VALUE_TYPE cst; + + if (! builtin_dconsts_init) + init_builtin_dconsts (); + real_convert (&cst, TYPE_MODE (type), &dconste); + return build_real (type, cst); + } + + /* Attempt to evaluate exp at compile-time. */ + if (flag_unsafe_math_optimizations + && TREE_CODE (arg) == REAL_CST + && ! TREE_CONSTANT_OVERFLOW (arg)) + { + REAL_VALUE_TYPE cint; + REAL_VALUE_TYPE c; + HOST_WIDE_INT n; + + c = TREE_REAL_CST (arg); + n = real_to_integer (&c); + real_from_integer (&cint, VOIDmode, n, + n < 0 ? -1 : 0, 0); + if (real_identical (&c, &cint)) + { + REAL_VALUE_TYPE x; + + if (! builtin_dconsts_init) + init_builtin_dconsts (); + real_powi (&x, TYPE_MODE (type), &dconste, n); + return build_real (type, x); + } + } + /* Optimize exp(log(x)) = x. */ fcode = builtin_mathfn_code (arg); if (flag_unsafe_math_optimizations @@ -5301,6 +5356,53 @@ fold_builtin (exp) } break; + case BUILT_IN_TAN: + case BUILT_IN_TANF: + case BUILT_IN_TANL: + if (validate_arglist (arglist, REAL_TYPE, VOID_TYPE)) + { + enum built_in_function fcode; + tree arg = TREE_VALUE (arglist); + + /* Optimize tan(0.0) = 0.0. */ + if (real_zerop (arg)) + return arg; + + /* Optimize tan(atan(x)) = x. */ + fcode = builtin_mathfn_code (arg); + if (flag_unsafe_math_optimizations + && (fcode == BUILT_IN_ATAN + || fcode == BUILT_IN_ATANF + || fcode == BUILT_IN_ATANL)) + return TREE_VALUE (TREE_OPERAND (arg, 1)); + } + break; + + case BUILT_IN_ATAN: + case BUILT_IN_ATANF: + case BUILT_IN_ATANL: + if (validate_arglist (arglist, REAL_TYPE, VOID_TYPE)) + { + tree arg = TREE_VALUE (arglist); + + /* Optimize atan(0.0) = 0.0. */ + if (real_zerop (arg)) + return arg; + + /* Optimize atan(1.0) = pi/4. */ + if (real_onep (arg)) + { + REAL_VALUE_TYPE cst; + + if (! builtin_dconsts_init) + init_builtin_dconsts (); + real_convert (&cst, TYPE_MODE (type), &dconstpi); + cst.exp -= 2; + return build_real (type, cst); + } + } + break; + case BUILT_IN_POW: case BUILT_IN_POWF: case BUILT_IN_POWL: @@ -5387,7 +5489,7 @@ fold_builtin (exp) REAL_VALUE_TYPE cint; HOST_WIDE_INT n; - n = real_to_integer(&c); + n = real_to_integer (&c); real_from_integer (&cint, VOIDmode, n, n < 0 ? -1 : 0, 0); if (real_identical (&c, &cint)) |