Hi. This patch includes implementation of new function roundeven along with two utility functions. The patch bootstraps on x86_64-linux-gnu and passes regression tests.
Thanks, Tejas gcc/ChangeLog: 2019-06-12 Tejas Joshi <tejasjoshi9...@gmail.com> * builtins.c (mathfn_built_in_2): Added CASE_MATHFN for ROUNDEVEN. * builtins.def: Added function definitions for roundeven function variants. * fold-const-call.c (fold_const_call_ss): Added case for function call and fold_const_conversion call for roundeven function. * fold-const.c (negate_mathfn_p): Added case for roundeven function. (tree_call_nonnegative_warnv_p): Added case for roundeven function. (integer_valued_real_call_p): Added case for roundeven function. * real.c (is_even): New function. Returns true if real number is even, otherwise returns false. (is_halfway_below): New function. Returns true if real number is halfway between two integers, else return false. (real_roundeven): New function. Round real number to nearest integer, rounding halfway cases towards even. * real.h (real_value): Added descriptive comments. Added function declaration for roundeven function. gcc/testsuite/ChangeLog: 2019-06-12 Tejas Joshi <tejasjoshi9...@gmail.com> * gcc.dg/torture/builtin-round-roundeven.c: New test. * gcc.dg/torture/builtin-round-roundevenf128.c: New test.
diff --git a/gcc/builtins.c b/gcc/builtins.c index 3463ffb1539..85a945877a4 100644 --- a/gcc/builtins.c +++ b/gcc/builtins.c @@ -2085,6 +2085,7 @@ mathfn_built_in_2 (tree type, combined_fn fn) CASE_MATHFN (REMQUO) CASE_MATHFN_FLOATN (RINT) CASE_MATHFN_FLOATN (ROUND) + CASE_MATHFN (ROUNDEVEN) CASE_MATHFN (SCALB) CASE_MATHFN (SCALBLN) CASE_MATHFN (SCALBN) diff --git a/gcc/builtins.def b/gcc/builtins.def index 6d41bdb4f44..8bb7027aac7 100644 --- a/gcc/builtins.def +++ b/gcc/builtins.def @@ -542,12 +542,18 @@ DEF_C99_BUILTIN (BUILT_IN_RINTL, "rintl", BT_FN_LONGDOUBLE_LONGDOUBLE, AT #define RINT_TYPE(F) BT_FN_##F##_##F DEF_EXT_LIB_FLOATN_NX_BUILTINS (BUILT_IN_RINT, "rint", RINT_TYPE, ATTR_CONST_NOTHROW_LEAF_LIST) #undef RINT_TYPE +DEF_EXT_LIB_BUILTIN (BUILT_IN_ROUNDEVEN, "roundeven", BT_FN_DOUBLE_DOUBLE, ATTR_CONST_NOTHROW_LEAF_LIST) +DEF_EXT_LIB_BUILTIN (BUILT_IN_ROUNDEVENF, "roundevenf", BT_FN_FLOAT_FLOAT, ATTR_CONST_NOTHROW_LEAF_LIST) +DEF_EXT_LIB_BUILTIN (BUILT_IN_ROUNDEVENL, "roundevenl", BT_FN_LONGDOUBLE_LONGDOUBLE, ATTR_CONST_NOTHROW_LEAF_LIST) DEF_C99_BUILTIN (BUILT_IN_ROUND, "round", BT_FN_DOUBLE_DOUBLE, ATTR_CONST_NOTHROW_LEAF_LIST) DEF_C99_BUILTIN (BUILT_IN_ROUNDF, "roundf", BT_FN_FLOAT_FLOAT, ATTR_CONST_NOTHROW_LEAF_LIST) DEF_C99_BUILTIN (BUILT_IN_ROUNDL, "roundl", BT_FN_LONGDOUBLE_LONGDOUBLE, ATTR_CONST_NOTHROW_LEAF_LIST) #define ROUND_TYPE(F) BT_FN_##F##_##F DEF_EXT_LIB_FLOATN_NX_BUILTINS (BUILT_IN_ROUND, "round", ROUND_TYPE, ATTR_CONST_NOTHROW_LEAF_LIST) #undef ROUND_TYPE +#define ROUNDEVEN_TYPE(F) BT_FN_##F##_##F +DEF_EXT_LIB_FLOATN_NX_BUILTINS (BUILT_IN_ROUNDEVEN, "roundeven", ROUNDEVEN_TYPE, ATTR_CONST_NOTHROW_LEAF_LIST) +#undef ROUNDEVEN_TYPE DEF_EXT_LIB_BUILTIN (BUILT_IN_SCALB, "scalb", BT_FN_DOUBLE_DOUBLE_DOUBLE, ATTR_MATHFN_FPROUNDING_ERRNO) DEF_EXT_LIB_BUILTIN (BUILT_IN_SCALBF, "scalbf", BT_FN_FLOAT_FLOAT_FLOAT, ATTR_MATHFN_FPROUNDING_ERRNO) DEF_EXT_LIB_BUILTIN (BUILT_IN_SCALBL, "scalbl", BT_FN_LONGDOUBLE_LONGDOUBLE_LONGDOUBLE, ATTR_MATHFN_FPROUNDING_ERRNO) diff --git a/gcc/fold-const-call.c b/gcc/fold-const-call.c index 702c8b4057a..d9b546e6803 100644 --- a/gcc/fold-const-call.c +++ b/gcc/fold-const-call.c @@ -836,6 +836,15 @@ fold_const_call_ss (real_value *result, combined_fn fn, } return false; + CASE_CFN_ROUNDEVEN: + CASE_CFN_ROUNDEVEN_FN: + if (!REAL_VALUE_ISNAN (*arg) || !flag_errno_math) + { + real_roundeven (result, format, arg); + return true; + } + return false; + CASE_CFN_LOGB: return fold_const_logb (result, arg, format); @@ -898,6 +907,10 @@ fold_const_call_ss (wide_int *result, combined_fn fn, return fold_const_conversion (result, real_round, arg, precision, format); + CASE_CFN_ROUNDEVEN: + CASE_CFN_ROUNDEVEN_FN: + return fold_const_conversion (result, real_roundeven, arg, precision, format); + CASE_CFN_IRINT: CASE_CFN_LRINT: CASE_CFN_LLRINT: diff --git a/gcc/fold-const.c b/gcc/fold-const.c index 0ca472d422f..07d82a17e25 100644 --- a/gcc/fold-const.c +++ b/gcc/fold-const.c @@ -329,6 +329,8 @@ negate_mathfn_p (combined_fn fn) CASE_CFN_LLROUND: CASE_CFN_LROUND: CASE_CFN_ROUND: + CASE_CFN_ROUNDEVEN: + CASE_CFN_ROUNDEVEN_FN: CASE_CFN_SIN: CASE_CFN_SINH: CASE_CFN_TAN: @@ -13063,6 +13065,8 @@ tree_call_nonnegative_warnv_p (tree type, combined_fn fn, tree arg0, tree arg1, CASE_CFN_RINT_FN: CASE_CFN_ROUND: CASE_CFN_ROUND_FN: + CASE_CFN_ROUNDEVEN: + CASE_CFN_ROUNDEVEN_FN: CASE_CFN_SCALB: CASE_CFN_SCALBLN: CASE_CFN_SCALBN: @@ -13586,6 +13590,8 @@ integer_valued_real_call_p (combined_fn fn, tree arg0, tree arg1, int depth) CASE_CFN_RINT_FN: CASE_CFN_ROUND: CASE_CFN_ROUND_FN: + CASE_CFN_ROUNDEVEN: + CASE_CFN_ROUNDEVEN_FN: CASE_CFN_TRUNC: CASE_CFN_TRUNC_FN: return true; diff --git a/gcc/real.c b/gcc/real.c index 0164f097a53..ab71430709f 100644 --- a/gcc/real.c +++ b/gcc/real.c @@ -5010,6 +5010,89 @@ real_round (REAL_VALUE_TYPE *r, format_helper fmt, real_convert (r, fmt, r); } +/* Return true including 0 if integer part of R is even, else return + false. The function is not valid for rvc_inf and rvc_nan classes. */ + +bool +is_even (REAL_VALUE_TYPE *r) +{ + gcc_assert (r->cl != rvc_inf); + gcc_assert (r->cl != rvc_nan); + + if (r->cl == rvc_zero) + return true; + + /* For (-1,1), number is even. */ + if (REAL_EXP (r) <= 0) + return true; + + /* Check lowest bit, if not set, return true. */ + else if (REAL_EXP (r) <= SIGNIFICAND_BITS) + { + unsigned int n = SIGNIFICAND_BITS - REAL_EXP (r); + int w = n / HOST_BITS_PER_LONG; + + unsigned long num = ((unsigned long)1 << (n % HOST_BITS_PER_LONG)); + + if ((r->sig[w] & num) == 0) + return true; + } + + else + return true; + + return false; +} + +/* Return true if R is halfway between two integers, else return + false. The function is not valid for rvc_inf and rvc_nan classes. */ + +bool +is_halfway_below (const REAL_VALUE_TYPE *r) +{ + gcc_assert (r->cl != rvc_inf); + gcc_assert (r->cl != rvc_nan); + int i; + + /* For numbers (-0.5,0) and (0,0.5). */ + if (REAL_EXP (r) < 0) + return false; + + else if (REAL_EXP (r) < SIGNIFICAND_BITS) + { + unsigned int n = SIGNIFICAND_BITS - REAL_EXP (r) - 1; + int w = n / HOST_BITS_PER_LONG; + + for (i = 0; i < w; ++i) + if (r->sig[i] != 0) + return false; + + unsigned long num = ((unsigned long)1 << (n % HOST_BITS_PER_LONG)); + + if (((r->sig[w] & num) != 0) && ((r->sig[w] & (num-1)) == 0)) + return true; + } + return false; +} + +/* Round X to nearest integer, rounding halfway cases towards even. */ + +void +real_roundeven (REAL_VALUE_TYPE *r, format_helper fmt, + const REAL_VALUE_TYPE *x) +{ + if (is_halfway_below (x)) + { + do_add (r, x, &dconsthalf, x->sign); + if (!is_even (r)) + do_add (r, r, &dconstm1, x->sign); + if (fmt) + real_convert (r, fmt, r); + } + else + real_round (r, fmt, x); +} + /* Set the sign of R to the sign of X. */ void diff --git a/gcc/real.h b/gcc/real.h index 95b9db83d24..76889bff0ea 100644 --- a/gcc/real.h +++ b/gcc/real.h @@ -41,11 +41,18 @@ struct GTY(()) real_value { sure they're packed together, otherwise REAL_VALUE_TYPE_SIZE will be miscomputed. */ unsigned int /* ENUM_BITFIELD (real_value_class) */ cl : 2; + /* 1 if number is decimal floating point */ unsigned int decimal : 1; + /* 1 if number is negative */ unsigned int sign : 1; + /* 1 if number is signalling */ unsigned int signalling : 1; + /* 1 if number is canonical + All are generally used for handling cases in real.c */ unsigned int canonical : 1; + /* unbiased exponent of the number */ unsigned int uexp : EXP_BITS; + /* significand of the number */ unsigned long sig[SIGSZ]; }; @@ -500,6 +507,8 @@ extern void real_ceil (REAL_VALUE_TYPE *, format_helper, const REAL_VALUE_TYPE *); extern void real_round (REAL_VALUE_TYPE *, format_helper, const REAL_VALUE_TYPE *); +extern void real_roundeven (REAL_VALUE_TYPE *, format_helper, + const REAL_VALUE_TYPE *); /* Set the sign of R to the sign of X. */ extern void real_copysign (REAL_VALUE_TYPE *, const REAL_VALUE_TYPE *); diff --git a/gcc/testsuite/gcc.dg/torture/builtin-round-roundeven.c b/gcc/testsuite/gcc.dg/torture/builtin-round-roundeven.c new file mode 100644 index 00000000000..f75adf6ec8a --- /dev/null +++ b/gcc/testsuite/gcc.dg/torture/builtin-round-roundeven.c @@ -0,0 +1,23 @@ +/* { dg-do link } */ + +extern int link_error (int); + +#define TEST(FN, VALUE, RESULT) \ + if (__builtin_##FN (VALUE) != RESULT) link_error (__LINE__); + +int +main (void) +{ + TEST(roundeven, 0, 0); + TEST(roundeven, 0.5, 0); + TEST(roundeven, -0.5, 0); + TEST(roundeven, 6, 6); + TEST(roundeven, -8, -8); + TEST(roundeven, 2.5, 2); + TEST(roundeven, 3.5, 4); + TEST(roundeven, -1.5, -2); + TEST(roundeven, 3.499, 3); + TEST(roundeven, 3.501, 4); + + return 0; +} \ No newline at end of file diff --git a/gcc/testsuite/gcc.dg/torture/builtin-round-roundevenf128.c b/gcc/testsuite/gcc.dg/torture/builtin-round-roundevenf128.c new file mode 100644 index 00000000000..592bad49623 --- /dev/null +++ b/gcc/testsuite/gcc.dg/torture/builtin-round-roundevenf128.c @@ -0,0 +1,20 @@ +/* { dg-do link } */ +/* { dg-add-options float128 } */ +/* { dg-require-effective-target float128 } */ + +extern int link_error (int); + +#define TEST(FN, VALUE, RESULT) \ + if (__builtin_##FN##f128 (VALUE) != RESULT) link_error (__LINE__); + +int +main (void) +{ + TEST(roundeven, (0x1p64+0.5f128), (0x1p64f128)); + TEST(roundeven, (0x1p63+0.5f128), (0x1p63f128)); + TEST(roundeven, (0x1p63-0.5f128), (0x1p63f128)); + TEST(roundeven, (0x1p64-0.5f128), (0x1p64f128)); + TEST(roundeven, (0x1p64+0.501f128), (0x1p64+1.0f128)); + TEST(roundeven, (0x1.C00000000000039A5653p1f128), (0x1p2f128)) + return 0; +} \ No newline at end of file