===================================================================
@@ -6333,18 +6333,25 @@ In C it is possible to use shifting oper
integer-type vectors. The operation is defined as following: @code{@{a0,
a1, @dots{}, an@} >> @{b0, b1, @dots{}, bn@} == @{a0 >> b0, a1 >> b1,
@dots{}, an >> bn@}}@. Vector operands must have the same number of
-elements. Additionally second operands can be a scalar integer in which
-case the scalar is converted to the type used by the vector operand (with
-possible truncation) and each element of this new vector is the scalar's
-value.
+elements.
+
+For the convenience in C it is allowed to use a binary vector operation
+where one operand is a scalar. In that case the compiler will transform
+the scalar operand into a vector where each element is the scalar from
+the operation. The transformation will happen only if the scalar could be
+safely converted to the vector-element type.
Consider the following code.
@smallexample
typedef int v4si __attribute__ ((vector_size (16)));
-v4si a, b;
+v4si a, b, c;
+long l;
+
+a = b + 1; /* a = b + @{1,1,1,1@}; */
+a = 2 * b; /* a = @{2,2,2,2@} * b; */
-b = a >> 1; /* b = a >> @{1,1,1,1@}; */
+a = l + a; /* Error, cannot convert long to int. */
@end smallexample
In C vectors can be subscripted as if the vector were an array with
===================================================================
@@ -0,0 +1,85 @@
+#define vector(elcount, type) \
+__attribute__((vector_size((elcount)*sizeof(type)))) type
+
+#define vidx(type, vec, idx) (*((type *) &(vec) + idx))
+
+#define operl(a, b, op) (a op b)
+#define operr(a, b, op) (b op a)
+
+#define check(type, count, vec0, vec1, num, op, lr) \
+do {\
+ int __i; \
+ for (__i = 0; __i < count; __i++) {\
+ if (vidx (type, vec1, __i) != oper##lr (num, vidx (type, vec0, __i), op)) \
+ __builtin_abort (); \
+ }\
+} while (0)
+
+#define veccompare(type, count, v0, v1) \
+do {\
+ int __i; \
+ for (__i = 0; __i < count; __i++) { \
+ if (vidx (type, v0, __i) != vidx (type, v1, __i)) \
+ __builtin_abort (); \
+ } \
+} while (0)
+
+
+int main (int argc, char *argv[]) {
+#define fvec_2 (vector(4, float)){2., 2., 2., 2.}
+#define dvec_2 (vector(2, double)){2., 2.}
+
+
+ vector(8, short) v0 = {argc, 1,2,3,4,5,6,7};
+ vector(8, short) v1;
+
+ vector(4, float) f0 = {1., 2., 3., 4.};
+ vector(4, float) f1, f2;
+
+ vector(2, double) d0 = {1., 2.};
+ vector(2, double) d1, d2;
+
+
+
+ v1 = 2 + v0; check (short, 8, v0, v1, 2, +, l);
+ v1 = 2 - v0; check (short, 8, v0, v1, 2, -, l);
+ v1 = 2 * v0; check (short, 8, v0, v1, 2, *, l);
+ v1 = 2 / v0; check (short, 8, v0, v1, 2, /, l);
+ v1 = 2 % v0; check (short, 8, v0, v1, 2, %, l);
+ v1 = 2 ^ v0; check (short, 8, v0, v1, 2, ^, l);
+ v1 = 2 & v0; check (short, 8, v0, v1, 2, &, l);
+ v1 = 2 | v0; check (short, 8, v0, v1, 2, |, l);
+ v1 = 2 << v0; check (short, 8, v0, v1, 2, <<, l);
+ v1 = 2 >> v0; check (short, 8, v0, v1, 2, >>, l);
+
+ v1 = v0 + 2; check (short, 8, v0, v1, 2, +, r);
+ v1 = v0 - 2; check (short, 8, v0, v1, 2, -, r);
+ v1 = v0 * 2; check (short, 8, v0, v1, 2, *, r);
+ v1 = v0 / 2; check (short, 8, v0, v1, 2, /, r);
+ v1 = v0 % 2; check (short, 8, v0, v1, 2, %, r);
+ v1 = v0 ^ 2; check (short, 8, v0, v1, 2, ^, r);
+ v1 = v0 & 2; check (short, 8, v0, v1, 2, &, r);
+ v1 = v0 | 2; check (short, 8, v0, v1, 2, |, r);
+
+ f1 = 2. + f0; f2 = fvec_2 + f0; veccompare (float, 4, f1, f2);
+ f1 = 2. - f0; f2 = fvec_2 - f0; veccompare (float, 4, f1, f2);
+ f1 = 2. * f0; f2 = fvec_2 * f0; veccompare (float, 4, f1, f2);
+ f1 = 2. / f0; f2 = fvec_2 / f0; veccompare (float, 4, f1, f2);
+
+ f1 = f0 + 2.; f2 = f0 + fvec_2; veccompare (float, 4, f1, f2);
+ f1 = f0 - 2.; f2 = f0 - fvec_2; veccompare (float, 4, f1, f2);
+ f1 = f0 * 2.; f2 = f0 * fvec_2; veccompare (float, 4, f1, f2);
+ f1 = f0 / 2.; f2 = f0 / fvec_2; veccompare (float, 4, f1, f2);
+
+ d1 = 2. + d0; d2 = dvec_2 + d0; veccompare (double, 2, d1, d2);
+ d1 = 2. - d0; d2 = dvec_2 - d0; veccompare (double, 2, d1, d2);
+ d1 = 2. * d0; d2 = dvec_2 * d0; veccompare (double, 2, d1, d2);
+ d1 = 2. / d0; d2 = dvec_2 / d0; veccompare (double, 2, d1, d2);
+
+ d1 = d0 + 2.; d2 = d0 + dvec_2; veccompare (double, 2, d1, d2);
+ d1 = d0 - 2.; d2 = d0 - dvec_2; veccompare (double, 2, d1, d2);
+ d1 = d0 * 2.; d2 = d0 * dvec_2; veccompare (double, 2, d1, d2);
+ d1 = d0 / 2.; d2 = d0 / dvec_2; veccompare (double, 2, d1, d2);
+
+ return 0;
+}
===================================================================
@@ -0,0 +1,62 @@
+#define vector(elcount, type) \
+__attribute__((vector_size((elcount)*sizeof(type)))) type
+
+#define vidx(type, vec, idx) (*((type *) &(vec) + idx))
+
+#define operl(a, b, op) (a op b)
+#define operr(a, b, op) (b op a)
+
+#define check(type, count, vec0, vec1, num, op, lr) \
+do {\
+ int __i; \
+ for (__i = 0; __i < count; __i++) {\
+ if (vidx (type, vec1, __i) != oper##lr (num, vidx (type, vec0, __i), op)) \
+ __builtin_abort (); \
+ }\
+} while (0)
+
+#define veccompare(type, count, v0, v1) \
+do {\
+ int __i; \
+ for (__i = 0; __i < count; __i++) { \
+ if (vidx (type, v0, __i) != vidx (type, v1, __i)) \
+ __builtin_abort (); \
+ } \
+} while (0)
+
+
+long __attribute__ ((noinline)) vlng () { return (long)42; }
+int __attribute__ ((noinline)) vint () { return (int) 43; }
+short __attribute__ ((noinline)) vsrt () { return (short)42; }
+char __attribute__ ((noinline)) vchr () { return (char)42; }
+
+
+int main (int argc, char *argv[]) {
+ vector(16, char) c0 = {argc, 1,2,3,4,5,6,7, argc, 1,2,3,4,5,6,7};
+ vector(16, char) c1;
+
+ vector(8, short) s0 = {argc, 1,2,3,4,5,6,7};
+ vector(8, short) s1;
+
+ vector(4, int) i0 = {argc, 1, 2, 3};
+ vector(4, int) i1;
+
+ vector(2, long) l0 = {argc, 1};
+ vector(2, long) l1;
+
+ c1 = vchr() + c0; check (char, 16, c0, c1, vchr(), +, l);
+
+ s1 = vsrt() + s0; check (short, 8, s0, s1, vsrt(), +, l);
+ s1 = vchr() + s0; check (short, 8, s0, s1, vchr(), +, l);
+
+ i1 = vint() * i0; check (int, 4, i0, i1, vint(), *, l);
+ i1 = vsrt() * i0; check (int, 4, i0, i1, vsrt(), *, l);
+ i1 = vchr() * i0; check (int, 4, i0, i1, vchr(), *, l);
+
+ l1 = vlng() * l0; check (long, 2, l0, l1, vlng(), *, l);
+ l1 = vint() * l0; check (long, 2, l0, l1, vint(), *, l);
+ l1 = vsrt() * l0; check (long, 2, l0, l1, vsrt(), *, l);
+ l1 = vchr() * l0; check (long, 2, l0, l1, vchr(), *, l);
+
+ return 0;
+}
===================================================================
@@ -0,0 +1,39 @@
+/* { dg-do compile } */
+#define vector(elcount, type) \
+__attribute__((vector_size((elcount)*sizeof(type)))) type
+
+#define vidx(type, vec, idx) (*((type *) &(vec) + idx))
+
+
+extern float sfl;
+extern int sint;
+
+int main (int argc, char *argv[]) {
+ vector(8, short) v0 = {argc, 1,2,3,4,5,6,7};
+ vector(8, short) v1;
+
+ vector(4, float) f0 = {1., 2., 3., 4.};
+ vector(4, float) f1, f2;
+
+ vector(4, int) i0 = {1,2,3,4};
+ vector(4, int) i1, i2;
+
+
+ int i = 12;
+ double d = 3.;
+
+ v1 = i + v0; /* { dg-error "conversion of scalar to vector" } */
+ v1 = 99999 + v0; /* { dg-error "conversion of scalar to vector" } */
+
+ f1 = d + f0; /* { dg-error "truncating floating point" } */
+ f1 = 1.3 + f0; /* { dg-error "truncating floating point" } */
+
+ /* convert.c should take care of this. */
+ i1 = sfl + i0; /* { dg-error "can't convert value to a vector" } */
+ i1 = 1.5 + i0; /* { dg-error "can't convert value to a vector" } */
+ v1 = d + v0; /* { dg-error "can't convert value to a vector" } */
+ f1 = sint + f0; /* { dg-error "can't convert between vector values of different size" } */
+
+
+ return 0;
+}
===================================================================
@@ -51,6 +51,14 @@ enum impl_conv {
ic_return
};
+/* Possibe cases of scalar_to_vector conversion. */
+enum stv_conv {
+ stv_error,
+ stv_nothing,
+ stv_firstarg,
+ stv_secondarg
+};
+
/* Whether we are building a boolean conversion inside
convert_for_assignment, or some other late binary operation. If
build_binary_op is called (from code shared with C++) in this case,
@@ -2156,7 +2164,7 @@ build_component_ref (location_t loc, tre
/* Chain the COMPONENT_REFs if necessary down to the FIELD.
This might be better solved in future the way the C++ front
end does it - by giving the anonymous entities each a
- separate name and type, and then have build_component_ref
+ /edseparate name and type, and then have build_component_ref
recursively call itself. We can't do that here. */
do
{
@@ -9387,6 +9395,112 @@ push_cleanup (tree decl, tree cleanup, b
TREE_OPERAND (stmt, 0) = list;
STATEMENT_LIST_STMT_EXPR (list) = stmt_expr;
}
+
+/* Return true if expression EXPR can be converted to the
+ vector type TYPE preserving its value. */
+static bool
+expr_fits_type_p (tree expr, tree type)
+{
+ enum machine_mode mode = TYPE_MODE (TREE_TYPE (type));
+ if (TYPE_MODE (TREE_TYPE (expr)) == mode)
+ return true;
+
+ if (TREE_CODE (expr) == INTEGER_CST)
+ return int_fits_type_p (expr, TREE_TYPE (type));
+ else if (TREE_CODE (TREE_TYPE (expr)) == INTEGER_TYPE)
+ return !tree_int_cst_lt
+ (TYPE_SIZE (TREE_TYPE (type)),
+ TYPE_SIZE (TREE_TYPE (expr)));
+ else if (TREE_CODE (expr) == REAL_CST)
+ {
+ REAL_VALUE_TYPE c, c1;
+ c = TREE_REAL_CST (expr);
+ real_convert (&c1, mode, &c);
+ return real_identical (&c, &c1);
+ }
+ else if (TREE_CODE (TREE_TYPE (expr)) == REAL_TYPE)
+ return (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (expr)))
+ <= GET_MODE_SIZE (mode));
+ return false;
+}
+
+/* Convert scalar to vector for the range of operations.
+ Function can return:
+ stv_error -- Error occured
+ stv_nothing -- Nothing happened
+ stv_firstarg -- First argument must be expanded
+ stv_secondarg -- Second argument must be expanded */
+static enum stv_conv
+scalar_to_vector (location_t loc, enum tree_code code, tree op0, tree op1)
+{
+ tree type0 = TREE_TYPE (op0);
+ tree type1 = TREE_TYPE (op1);
+ bool integer_only_op = false;
+ enum stv_conv ret = stv_firstarg;
+
+ switch (code)
+ {
+ case RSHIFT_EXPR:
+ case LSHIFT_EXPR:
+ if (TREE_CODE (type0) == INTEGER_TYPE)
+ if (!expr_fits_type_p (op0, type1))
+ {
+ error_at (loc, "conversion of scalar to vector "
+ "involves truncation");
+ return stv_error;
+ }
+ return stv_firstarg;
+
+ case BIT_IOR_EXPR:
+ case BIT_XOR_EXPR:
+ case BIT_AND_EXPR:
+ integer_only_op = true;
+ /* ... fall through ... */
+
+ case PLUS_EXPR:
+ case MINUS_EXPR:
+ case MULT_EXPR:
+ case TRUNC_DIV_EXPR:
+ case TRUNC_MOD_EXPR:
+ case RDIV_EXPR:
+ if (TREE_CODE (type0) == VECTOR_TYPE)
+ {
+ tree tmp;
+ ret = stv_secondarg;
+ /* Swap TYPE0 with TYPE1 and OP0 with OP1 */
+ tmp = type0; type0 = type1; type1 = tmp;
+ tmp = op0; op0 = op1; op1 = tmp;
+ }
+
+ if (TREE_CODE (type0) == INTEGER_TYPE
+ && TREE_CODE (TREE_TYPE (type1)) == INTEGER_TYPE)
+ {
+ if (!expr_fits_type_p (op0, type1))
+ {
+ error_at (loc, "conversion of scalar to vector "
+ "involves truncation");
+ return stv_error;
+ }
+ return ret;
+ }
+ else if (!integer_only_op
+ && TREE_CODE (type0) == REAL_TYPE
+ && SCALAR_FLOAT_TYPE_P (TREE_TYPE (type1)))
+ {
+ if (!expr_fits_type_p (op0, type1))
+ {
+ error_at (loc, "truncating floating point constant to "
+ "vector precision does not preserve value");
+ return stv_error;
+ }
+ return ret;
+ }
+ default:
+ break;
+ }
+
+ return stv_nothing;
+}
/* Build a binary-operation expression without default conversions.
CODE is the kind of expression to build.
@@ -9498,7 +9612,10 @@ build_binary_op (location_t location, en
else
int_const = int_const_or_overflow = false;
- if (convert_p)
+ /* Do not apply default conversion in mixed vector/scalar expression. */
+ if (convert_p
+ && !((TREE_CODE (TREE_TYPE (op0)) == VECTOR_TYPE)
+ != (TREE_CODE (TREE_TYPE (op1)) == VECTOR_TYPE)))
{
op0 = default_conversion (op0);
op1 = default_conversion (op1);
@@ -9570,6 +9687,41 @@ build_binary_op (location_t location, en
objc_ok = objc_compare_types (type0, type1, -3, NULL_TREE);
+ /* In case when one of the operands of the binary operation is
+ a vector and another is a scalar -- convert scalar to vector. */
+ if ((code0 == VECTOR_TYPE) != (code1 == VECTOR_TYPE))
+ {
+ enum stv_conv convert_flag = scalar_to_vector (location, code, op0, op1);
+
+ switch (convert_flag)
+ {
+ case stv_error:
+ return error_mark_node;
+ case stv_firstarg:
+ {
+ tree sc = save_expr (op0);
+ sc = convert (TREE_TYPE (type1), sc);
+ op0 = build_vector_from_val (type1, sc);
+ orig_type0 = type0 = TREE_TYPE (op0);
+ code0 = TREE_CODE (type0);
+ converted = 1;
+ break;
+ }
+ case stv_secondarg:
+ {
+ tree sc = save_expr (op1);
+ sc = convert (TREE_TYPE (type0), sc);
+ op1 = build_vector_from_val (type0, sc);
+ orig_type1 = type1 = TREE_TYPE (op1);
+ code1 = TREE_CODE (type1);
+ converted = 1;
+ break;
+ }
+ default:
+ break;
+ }
+ }
+
switch (code)
{
case PLUS_EXPR:
Thanks for the comments. default_conversion is switched off for the vector/scalar case. bitwise operations are added. new testcase is created. 2010-11-01 Artjoms Sinkarovs <artyom.shinakroff@gmail.com> /gcc * c-typeck.c (expr_fits_type_p): New function. Check if expression fits into the type considering constants. (scalar_to_vector): New function. Try scalar to vector conversion. (build_binary_op): Adjust. * doc/extend.texi: Description of scalar to vector expansion. /gcc/testsuite * gcc.c-torture/execute/scal-to-vec1.c: New test. * gcc.c-torture/execute/scal-to-vec2.c: New test. * gcc.dg/scal-to-vec1.c: New test. bootstrapped and tested on x86_64_unknown-linux OK? On Sat, Nov 6, 2010 at 5:44 PM, Joseph S. Myers <joseph@codesourcery.com> wrote: > On Wed, 3 Nov 2010, Artem Shinkarov wrote: > >> @@ -9387,6 +9387,104 @@ push_cleanup (tree decl, tree cleanup, b >> TREE_OPERAND (stmt, 0) = list; >> STATEMENT_LIST_STMT_EXPR (list) = stmt_expr; >> } >> + >> +/* Return true if expression EXPR can be converted to the >> + vectortype TYPE preserving its value. */ > > "vector type" (two words) > >> +static bool >> +expr_fits_type_p (tree expr, tree type) >> +{ > > I don't see anything here to handle removing widening conversions from > expr. Say you have a variable of type short - do you expect to be able to > do a binary operation between that variable and a vector of shorts? > Because the variable will have been converted to int. I don't see any > testcases in this area either. > > If you do want to allow that, rather than making this function smarter and > so making the language definition depend on how smart the compiler is > about seeing what conversions are safe I think it might be better to avoid > having build_binary_op calling default_conversion on the scalar operand in > a mixed vector/scalar operation. > >> +/* Convert scalar to vector for the range of operations. >> + Function can return: >> + -2 -- Error ocured > > "occurred" > >> + -1 -- Nothing happened >> + 0 -- First argument must be expanded >> + 1 -- Second argument must be expanded */ > > Please define an enum giving symbolic names to the possible return values, > rather than using magic constants. */ > >> + error_at (loc, "Conversion of scalar to vector " >> + "involves truncation"); > > Diagnostics should not start with capital letters. Likewise for all the > other diagnostics in this function. > > The patch does not seem to include any testcases for bitwise operations > (&^|). If they are meant to work with mixed scalar/vector operations > (which would be my expectation), then testcases are needed unless already > in the testsuite; if not, testcases are still needed and the documentation > needs to make clear they are not allowed. > > -- > Joseph S. Myers > joseph@codesourcery.com >