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Re: About GSOC.
- From: Tejas Joshi <tejasjoshi9673 at gmail dot com>
- To: gcc at gcc dot gnu dot org
- Date: Mon, 4 Feb 2019 22:55:50 +0530
- Subject: Re: About GSOC.
- References: <CACMrGjCeaZ7EoYqjLYiAJXjOtOfpJNo9zcbWhfarfkiLMN8YYA@mail.gmail.com> <CACMrGjCJ3r9+iNnFUOdajH+73HYHexv+mn7p_MHtn4jUn0d7-Q@mail.gmail.com> <ri6k1m9q6rm.fsf@suse.cz> <alpine.DEB.2.21.1810231631010.17157@digraph.polyomino.org.uk> <CACMrGjB6WLp0YS17b3prvbxvYnKtEsxhN3NOePN5SPVazNRM3A@mail.gmail.com> <alpine.DEB.2.21.1811161645480.12454@digraph.polyomino.org.uk> <CACMrGjC64UmP5-_hSiXyXrb2+cyqDqZ9iQMYJNn+mOKZ6G_LeQ@mail.gmail.com> <alpine.DEB.2.21.1901212257310.27116@digraph.polyomino.org.uk> <CACMrGjBw3-Xm1rHAanVUjYGC3SojJSgKZKL5B+HdkcTEOZ=Kkg@mail.gmail.com> <CACMrGjBBvv=taD6vCK9QcqQJYbGWJj_KSSeSBfnU_DRdcuonrw@mail.gmail.com> <alpine.DEB.2.21.1901231735280.25816@digraph.polyomino.org.uk> <CACMrGjC6NP5CE17M1gDf09B+2Gbufp3offHQmRX1D8hiWGrQ2Q@mail.gmail.com> <alpine.DEB.2.21.1901252130130.8264@digraph.polyomino.org.uk> <CACMrGjDxpwLcVGgAwTDN=LojT01dUTK03dCH54CR1wYFPjGjAg@mail.gmail.com> <CACMrGjARaj3Dy-PzSvTehLzchbDEdE8mbD0rH9Ko6Eu3mFERGg@mail.gmail.com> <CAAgBjMk+QBgY3YgMbuBaq--PkBWfN8jg42Fon1F6cbC2dRV2BA@mail.gmail.com> <CACMrGjC6Gk6UFr9T5iY0OgW5PJ92bB3tSrx59+D3FK+fMGYErQ@mail.gmail.com> <CAAgBjMk+8M2MYNdePb=rNfSkkCW=ZCezQPmqkMbYHe0nVJLzwQ@mail.gmail.com>
Hi.
Although now, I am unable to build the compiler.
The build exited returning status as:
DEF_INTERNAL_FLT_FN (ROUNDEVEN) has no associated built-in functions
I have added the entry in fold_const_call_ss() and do not find any
other place to add the case.
Here is the latest patch.
On Mon, 4 Feb 2019 at 22:14, Prathamesh Kulkarni
<prathamesh.kulkarni@linaro.org> wrote:
>
> On Mon, 4 Feb 2019 at 21:27, Tejas Joshi <tejasjoshi9673@gmail.com> wrote:
> >
> > Thanks.
> > > Did you add an entry for roundeven in builtins.def ?
> > Yes, I did.
> >
> > Find here the attached patch.diff for which I did the changes to
> > implement roundeven. There might be some unnecessary changes and some
> > necessary changes which have not been made.
> You haven't called roundeven() in the patch. You'll need to add an
> entry in fold_const_call_ss()
> similar to real_ceil, and probably in other places too.
>
> Thanks,
> Prathamesh
> >
> > Regards,
> > -Tejas
> >
> > On Mon, 4 Feb 2019 at 20:36, Prathamesh Kulkarni
> > <prathamesh.kulkarni@linaro.org> wrote:
> > >
> > > On Mon, 4 Feb 2019 at 20:10, Tejas Joshi <tejasjoshi9673@gmail.com> wrote:
> > > >
> > > > Hello.
> > > > I have implemented roundeven function in real.c as follows: (and
> > > > respective changes in real.h)
> > > It's a better idea to include all changes in patch instead of copy-pasting.
> > > Use the command:
> > > git diff > patch.diff
> > > which will create a file called "patch.diff" containing the changes
> > > and send it as an attachment.
> > > >
> > > > /* Round X to nearest even integer towards zero. */
> > > >
> > > > void
> > > > real_roundeven (REAL_VALUE_TYPE *r, format_helper fmt,
> > > > const REAL_VALUE_TYPE *x)
> > > > {
> > > > REAL_VALUE_TYPE t;
> > > >
> > > > do_fix_trunc (&t, x);
> > > > HOST_WIDE_INT i = real_to_integer (&t);
> > > > if(i % 2)
> > > > do_add (r, &t, &dconstm1, 0);
> > > > else
> > > > *r = t;
> > > > }
> > > >
> > > > Although I cant get it to test like
> > > >
> > > > int foo()
> > > > {
> > > > double x = __builtin_roundeven (3.5);
> > > > printf("%f",x);
> > > > return (int) x;
> > > > }
> > > > Because I do not know its dependencies through other files. I tried to
> > > > track them down by inspecting real_ceil function, but it also includes
> > > > other optimization procedures like folding. How do I know enough
> > > > declarations to be made in respective files?
> > > Did you add an entry for roundeven in builtins.def ?
> > >
> > > Thanks,
> > > Prathamesh
> > > >
> > > > Thanks.
> > > > -Tejas
> > > >
> > > > On Mon, 28 Jan 2019 at 22:33, Tejas Joshi <tejasjoshi9673@gmail.com> wrote:
> > > > >
> > > > > Hello.
> > > > > Representations of real numbers in real.c are a little complex to
> > > > > understand right now for me. I am still trying to understand them and
> > > > > figure them out using gdb and cscope. Though conventions are given in
> > > > > comments in real.c, I will still be trying to figure it out. The
> > > > > equation and its bitwise representation is not pretty elaborated in
> > > > > any documentation I could find.
> > > > >
> > > > > x = s * b^e * \sum_{k=1}^p f_k * b^{-k}
> > > > >
> > > > > where
> > > > > s = sign (+- 1)
> > > > > b = base or radix, here always 2
> > > > > e = exponent
> > > > > p = precision (the number of base-b digits in the significand)
> > > > > f_k = the digits of the significand.
> > > > >
> > > > > In mean time, I've tried real_round function to work like roundeven. I
> > > > > will try to submit a clean patch along with roundeven implemented
> > > > > separately with changes like in builtins.def, adding cases, etc.
> > > > >
> > > > > void
> > > > > real_round (REAL_VALUE_TYPE *r, format_helper fmt,
> > > > > const REAL_VALUE_TYPE *x)
> > > > > {
> > > > > #if 0
> > > > > do_add (r, x, &dconsthalf, x->sign);
> > > > > do_fix_trunc (r, r);
> > > > > if (fmt)
> > > > > real_convert (r, fmt, r);
> > > > > #endif
> > > > > fprintf (stderr, "\nhere\n");
> > > > > real_value z;
> > > > > do_fix_trunc (&z, x);
> > > > > HOST_WIDE_INT i = real_to_integer (&z);
> > > > > fprintf (stderr, "\n i = %ld\n", i);
> > > > > if (i % 2)
> > > > > do_add (r, &z, &dconstm1, 0);
> > > > > else
> > > > > *r = z;
> > > > > }
> > > > >
> > > > > Thanks.
> > > > > -Tejas
> > > > >
> > > > > On Sat, 26 Jan 2019 at 03:02, Joseph Myers <joseph@codesourcery.com> wrote:
> > > > > >
> > > > > > On Sat, 26 Jan 2019, Tejas Joshi wrote:
> > > > > >
> > > > > > > function with byte-byte comparison which also include mpfr. (Correct
> > > > > > > me if I am wrong.) What is the significance of mpfr related to these
> > > > > > > internal representations?
> > > > > >
> > > > > > real.c provides a fixed-size representation of floating-point numbers that
> > > > > > allows for various non-IEEE formats supported by GCC, and also allows
> > > > > > functions from dfp.c to be used for decimal floating-point formats.
> > > > > >
> > > > > > MPFR is used in GCC to provide operations that are nontrivial to
> > > > > > implement, especially those that are nontrivial to implement in such a
> > > > > > fixed-size context. real.c operations wrap around MPFR ones where
> > > > > > appropriate, doing whatever's needed in cases where there are non-IEEE
> > > > > > semantics or sets of values.
> > > > > >
> > > > > > --
> > > > > > Joseph S. Myers
> > > > > > joseph@codesourcery.com
diff --git a/gcc/builtins.c b/gcc/builtins.c
index 25e01e4092b..25282d2122d 100644
--- a/gcc/builtins.c
+++ b/gcc/builtins.c
@@ -2067,6 +2067,7 @@ mathfn_built_in_2 (tree type, combined_fn fn)
CASE_MATHFN (REMQUO)
CASE_MATHFN_FLOATN (RINT)
CASE_MATHFN_FLOATN (ROUND)
+ CASE_MATHFN_FLOATN (ROUNDEVEN)
CASE_MATHFN (SCALB)
CASE_MATHFN (SCALBLN)
CASE_MATHFN (SCALBN)
diff --git a/gcc/builtins.def b/gcc/builtins.def
index ef89729fd0c..f1b6830a49c 100644
--- a/gcc/builtins.def
+++ b/gcc/builtins.def
@@ -308,6 +308,7 @@ DEF_C99_BUILTIN (BUILT_IN_CBRT, "cbrt", BT_FN_DOUBLE_DOUBLE, ATTR_MATHFN_
DEF_C99_BUILTIN (BUILT_IN_CBRTF, "cbrtf", BT_FN_FLOAT_FLOAT, ATTR_MATHFN_FPROUNDING)
DEF_C99_BUILTIN (BUILT_IN_CBRTL, "cbrtl", BT_FN_LONGDOUBLE_LONGDOUBLE, ATTR_MATHFN_FPROUNDING)
DEF_LIB_BUILTIN (BUILT_IN_CEIL, "ceil", BT_FN_DOUBLE_DOUBLE, ATTR_CONST_NOTHROW_LEAF_LIST)
+DEF_EXT_LIB_BUILTIN (BUILT_IN_ROUNDEVEN, "roundeven", BT_FN_DOUBLE_DOUBLE, ATTR_CONST_NOTHROW_LEAF_LIST)
DEF_C99_C90RES_BUILTIN (BUILT_IN_CEILF, "ceilf", BT_FN_FLOAT_FLOAT, ATTR_CONST_NOTHROW_LEAF_LIST)
DEF_C99_C90RES_BUILTIN (BUILT_IN_CEILL, "ceill", BT_FN_LONGDOUBLE_LONGDOUBLE, ATTR_CONST_NOTHROW_LEAF_LIST)
#define CEIL_TYPE(F) BT_FN_##F##_##F
diff --git a/gcc/fold-const-call.c b/gcc/fold-const-call.c
index 06a420601c0..6f4fea63b0c 100644
--- a/gcc/fold-const-call.c
+++ b/gcc/fold-const-call.c
@@ -773,6 +773,16 @@ fold_const_call_ss (real_value *result, combined_fn fn,
CASE_CFN_CEIL_FN:
if (!REAL_VALUE_ISNAN (*arg) || !flag_errno_math)
{
+ fprintf (stderr, "\n");
+ fprintf (stderr, "cl: %u\n", arg->cl);
+ fprintf (stderr, "sign: %u\n", arg->sign);
+ fprintf (stderr, "signalling: %u\n", arg->signalling);
+ fprintf (stderr, "canonical: %u\n", arg->canonical);
+ fprintf (stderr, "uexp: %u\n", arg->uexp);
+
+ fprintf (stderr, "sig: ");
+ for (int i = 0; i < SIGSZ; i++)
+ fprintf (stderr, "%lx ", arg->sig[i]);
real_ceil (result, format, arg);
return true;
}
@@ -792,6 +802,15 @@ 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);
diff --git a/gcc/internal-fn.def b/gcc/internal-fn.def
index cda314e1121..b89918815f9 100644
--- a/gcc/internal-fn.def
+++ b/gcc/internal-fn.def
@@ -224,6 +224,7 @@ DEF_INTERNAL_FLT_FLOATN_FN (FLOOR, ECF_CONST, floor, unary)
DEF_INTERNAL_FLT_FLOATN_FN (NEARBYINT, ECF_CONST, nearbyint, unary)
DEF_INTERNAL_FLT_FLOATN_FN (RINT, ECF_CONST, rint, unary)
DEF_INTERNAL_FLT_FLOATN_FN (ROUND, ECF_CONST, round, unary)
+DEF_INTERNAL_FLT_FLOATN_FN (ROUNDEVEN, ECF_CONST, roundeven, unary)
DEF_INTERNAL_FLT_FLOATN_FN (TRUNC, ECF_CONST, btrunc, unary)
/* Binary math functions. */
diff --git a/gcc/optabs.def b/gcc/optabs.def
index 5a67f5eed5e..eb9e22acd8f 100644
--- a/gcc/optabs.def
+++ b/gcc/optabs.def
@@ -267,6 +267,7 @@ OPTAB_D (fnms_optab, "fnms$a4")
OPTAB_D (rint_optab, "rint$a2")
OPTAB_D (round_optab, "round$a2")
+OPTAB_D (roundeven_optab, "roundeven$a2")
OPTAB_D (floor_optab, "floor$a2")
OPTAB_D (ceil_optab, "ceil$a2")
OPTAB_D (btrunc_optab, "btrunc$a2")
diff --git a/gcc/real.c b/gcc/real.c
index f822ae82d61..9c57f50e8fc 100644
--- a/gcc/real.c
+++ b/gcc/real.c
@@ -1956,6 +1956,8 @@ real_to_hexadecimal (char *str, const REAL_VALUE_TYPE *r, size_t buf_size,
int
real_from_string (REAL_VALUE_TYPE *r, const char *str)
{
+ fprintf (stderr, "\nreal_from_string: str = %s\n", str);
+
int exp = 0;
bool sign = false;
@@ -5004,10 +5006,39 @@ void
real_round (REAL_VALUE_TYPE *r, format_helper fmt,
const REAL_VALUE_TYPE *x)
{
+#if 0
do_add (r, x, &dconsthalf, x->sign);
do_fix_trunc (r, r);
if (fmt)
real_convert (r, fmt, r);
+#endif
+ fprintf (stderr, "\nhere\n");
+ real_value z;
+ do_fix_trunc (&z, x);
+ HOST_WIDE_INT i = real_to_integer (&z);
+ fprintf (stderr, "\n i = %ld\n", i);
+ if (i % 2)
+ do_add (r, &z, &dconstm1, 0);
+ else
+ *r = z;
+}
+
+/* Round X to nearest even integer towards zero. */
+
+void
+real_roundeven (REAL_VALUE_TYPE *r, format_helper fmt,
+ const REAL_VALUE_TYPE *x)
+{
+ REAL_VALUE_TYPE t;
+
+ do_fix_trunc (&t, x);
+ HOST_WIDE_INT i = real_to_integer (&t);
+ fprintf (stderr, "\nhere\n");
+ fprintf (stderr, "\n i = %ld\n", i);
+ if(i % 2)
+ do_add (r, &t, &dconstm1, 0);
+ else
+ *r = t;
}
/* Set the sign of R to the sign of X. */
diff --git a/gcc/real.h b/gcc/real.h
index 0ce42565708..10898eae79e 100644
--- a/gcc/real.h
+++ b/gcc/real.h
@@ -499,6 +499,8 @@ 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/realmpfr.c b/gcc/realmpfr.c
index 10f05caaba3..4834fd017b1 100644
--- a/gcc/realmpfr.c
+++ b/gcc/realmpfr.c
@@ -98,6 +98,7 @@ real_from_mpfr (REAL_VALUE_TYPE *r, mpfr_srcptr m, const real_format *format,
mpfr_free_str (rstr);
+ fprintf (stderr, "\nreal_from_mpfr: buf = %s\n", buf);
real_from_string (r, buf);
}