Hello.
I am trying to add fadd function variants and as fadd takes two
arguments, the function should be called from fold_const_call_sss ().
The function is closely modeled on function calls and cases according
to real_nextafter (), also used gdb to look at backtrace. Although I
have made changes according to real_nextafter, the function real_fadd
is not called by the test program but real_nextafter does get called.
I cant find any other places to add calls for fadd. What is missing?
The patch is attached herewith.
int
main ()
{
float x;
x = __builtin_fadd (3.5,1.4);
}
Also, fadd function should not have faddf variant, but is introduced
only for the sake.
Thanks,
-Tejas
On Wed, 3 Jul 2019 at 18:29, Tejas Joshi wrote:
>
> Hello.
> Functions like fadd, faddl take two arguments, do the addition and
> return the answer in narrower precision than the argument type. The
> thing that might be helpful is using the do_add function directly, if
> appropriate?
> The thing to consider about narrowed down return type is how it can be
> achieved. The functions that operate on real numbers like real_round
> and so on, do not consider the return type and do calculations on the
> entire real number representation. So just defining these functions
> and their return type in builtins.def and other appropriate places
> would do the trick?
> like:
> BT_FN_FLOAT_DOUBLE_DOUBLE as return and argument type for FADD
>
> Or it has to be narrowed down by zeroing down the trailing
> out-of-precision bits?
> Also, if the addition or any one of the argument exceeds the return
> size, the integer part of the addition would not fit in the narrowed
> type. Like, 2^32 would easily fit in double but will lose its least
> significant bit in float and become 2^31. How these types are supposed
> to be handled?
>
> Thanks,
> -Tejas
diff --git a/gcc/builtin-types.def b/gcc/builtin-types.def
index e5c9e063c48..47cb81006e0 100644
--- a/gcc/builtin-types.def
+++ b/gcc/builtin-types.def
@@ -387,6 +387,8 @@ DEF_FUNCTION_TYPE_2 (BT_FN_VOID_UINT_PTR,
BT_VOID, BT_UINT, BT_PTR)
DEF_FUNCTION_TYPE_2 (BT_FN_FLOAT_FLOAT_FLOAT,
BT_FLOAT, BT_FLOAT, BT_FLOAT)
+DEF_FUNCTION_TYPE_2 (BT_FN_FLOAT_DOUBLE_DOUBLE,
+ BT_FLOAT, BT_DOUBLE, BT_DOUBLE)
DEF_FUNCTION_TYPE_2 (BT_FN_DOUBLE_DOUBLE_DOUBLE,
BT_DOUBLE, BT_DOUBLE, BT_DOUBLE)
DEF_FUNCTION_TYPE_2 (BT_FN_LONGDOUBLE_LONGDOUBLE_LONGDOUBLE,
diff --git a/gcc/builtins.c b/gcc/builtins.c
index 85a945877a4..371fb62b645 100644
--- a/gcc/builtins.c
+++ b/gcc/builtins.c
@@ -2035,6 +2035,7 @@ mathfn_built_in_2 (tree type, combined_fn fn)
CASE_MATHFN (EXP2)
CASE_MATHFN (EXPM1)
CASE_MATHFN (FABS)
+CASE_MATHFN (FADD)
CASE_MATHFN (FDIM)
CASE_MATHFN_FLOATN (FLOOR)
CASE_MATHFN_FLOATN (FMA)
diff --git a/gcc/builtins.def b/gcc/builtins.def
index 8bb7027aac7..1d065eae345 100644
--- a/gcc/builtins.def
+++ b/gcc/builtins.def
@@ -352,6 +352,9 @@ DEF_C99_C90RES_BUILTIN (BUILT_IN_FABSL, "fabsl", BT_FN_LONGDOUBLE_LONGDOUBLE, AT
#define FABS_TYPE(F) BT_FN_##F##_##F
DEF_EXT_LIB_FLOATN_NX_BUILTINS (BUILT_IN_FABS, "fabs", FABS_TYPE, ATTR_CONST_NOTHROW_LEAF_LIST)
#undef FABS_TYPE
+DEF_EXT_LIB_BUILTIN(BUILT_IN_FADD, "fadd", BT_FN_FLOAT_DOUBLE_DOUBLE, ATTR_CONST_NOTHROW_LEAF_LIST)
+DEF_EXT_LIB_BUILTIN(BUILT_IN_FADDF, "faddf", BT_FN_FLOAT_DOUBLE_DOUBLE, ATTR_CONST_NOTHROW_LEAF_LIST)
+DEF_EXT_LIB_BUILTIN(BUILT_IN_FADDL, "faddl", BT_FN_FLOAT_DOUBLE_DOUBLE, ATTR_CONST_NOTHROW_LEAF_LIST)
DEF_GCC_BUILTIN(BUILT_IN_FABSD32, "fabsd32", BT_FN_DFLOAT32_DFLOAT32, ATTR_CONST_NOTHROW_LEAF_LIST)
DEF_GCC_BUILTIN(BUILT_IN_FABSD64, "fabsd64", BT_FN_DFLOAT64_DFLOAT64, ATTR_CONST_NOTHROW_LEAF_LIST)
DEF_GCC_BUILTIN(BUILT_IN_FABSD128, "fabsd128", BT_FN_DFLOAT128_DFLOAT128, ATTR_CONST_NOTHROW_LEAF_LIST)
diff --git a/gcc/fold-const-call.c b/gcc/fold-const-call.c
index d9b546e6803..ee939f85005 100644
--- a/gcc/fold-const-call.c
+++ b/gcc/fold-const-call.c
@@ -570,6 +570,16 @@ fold_const_nextafter (real_value *result, const real_value *arg0,
return true;
}
+static bool
+fold_const_fadd (real_value* result, const real_value *arg0,
+ const real_value *arg1, const real_format *format)
+{
+ if (!real_fadd(result, format, arg0, arg1))
+return true;
+ else
+return false;
+}
+
/* Try to evaluate:
*RESULT = ldexp (*ARG0, ARG1)
@@ -1366,6 +1376,9 @@ fold_const_call_sss (real_value *result, combined_fn fn,
CASE_CFN_NEXTTOWARD:
return fold_const_nextafter (result, arg0, arg1, format);
+CASE_CFN_FADD:
+ return fold_const_fadd (result, arg0, arg1, format);
+
default:
return false;
}
diff --git a/gcc/real.c b/gcc/real.c
index ab71430709f..6379cd0bcdc 100644
--- a/gcc/real.c
+++ b/gcc/real.c
@@ -5093,6 +5093,17 @@ real_roundeven (REAL_VALUE_TYPE *r, format_helper fmt,
real_round (r, fmt, x);
}
+bool
+real_fadd (REAL_VALUE_TYPE *r, format_helper fmt,
+ const REAL_VALUE_TYPE *x, const REAL_VALUE_TYPE
