Shift operators working correctly

This commit is contained in:
Nick Gasson 2008-06-23 12:14:12 +01:00
parent d5cdb91d55
commit c9ace14c40
3 changed files with 36 additions and 5 deletions

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@ -127,6 +127,17 @@ static vhdl_expr *translate_relation(vhdl_expr *lhs, vhdl_expr *rhs,
return new vhdl_binop_expr(lhs, op, r_cast, vhdl_type::boolean()); return new vhdl_binop_expr(lhs, op, r_cast, vhdl_type::boolean());
} }
static vhdl_expr *translate_shift(vhdl_expr *lhs, vhdl_expr *rhs,
vhdl_binop_t op)
{
// The RHS must be an integer
vhdl_type integer(VHDL_TYPE_INTEGER);
vhdl_expr *r_cast = rhs->cast(&integer);
vhdl_type *rtype = new vhdl_type(*lhs->get_type());
return new vhdl_binop_expr(lhs, op, r_cast, rtype);
}
static vhdl_expr *translate_binary(ivl_expr_t e) static vhdl_expr *translate_binary(ivl_expr_t e)
{ {
vhdl_expr *lhs = translate_expr(ivl_expr_oper1(e)); vhdl_expr *lhs = translate_expr(ivl_expr_oper1(e));
@ -176,9 +187,9 @@ static vhdl_expr *translate_binary(ivl_expr_t e)
case '>': case '>':
return translate_relation(lhs, rhs, VHDL_BINOP_GT); return translate_relation(lhs, rhs, VHDL_BINOP_GT);
case 'l': case 'l':
return translate_numeric(lhs, rhs, VHDL_BINOP_SL); return translate_shift(lhs, rhs, VHDL_BINOP_SL);
case 'r': case 'r':
return translate_numeric(lhs, rhs, VHDL_BINOP_SR); return translate_shift(lhs, rhs, VHDL_BINOP_SR);
default: default:
error("No translation for binary opcode '%c'\n", error("No translation for binary opcode '%c'\n",
ivl_expr_opcode(e)); ivl_expr_opcode(e));

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@ -585,7 +585,7 @@ void vhdl_assign_stmt::emit(std::ofstream &of, int level) const
} }
vhdl_const_bits::vhdl_const_bits(const char *value, int width) vhdl_const_bits::vhdl_const_bits(const char *value, int width)
: vhdl_expr(vhdl_type::nsigned(width), true) : vhdl_expr(vhdl_type::nsigned(width), true), qualified_(false)
{ {
// Can't rely on value being NULL-terminated // Can't rely on value being NULL-terminated
while (width--) while (width--)
@ -604,20 +604,39 @@ vhdl_expr *vhdl_const_bits::cast(const vhdl_type *to)
return new vhdl_const_bit(lsb); return new vhdl_const_bit(lsb);
} }
else if (to->get_name() == VHDL_TYPE_STD_LOGIC_VECTOR) {
// Don't need to do anything
return this;
}
else if (to->get_name() == VHDL_TYPE_SIGNED
|| to->get_name() == VHDL_TYPE_UNSIGNED) {
// Might need to drop some bits (but not extend?)
assert(to->get_width() <= get_type()->get_width());
value_.resize(to->get_width());
return this;
}
else if (to->get_name() == VHDL_TYPE_INTEGER) {
// Need to explicitly qualify the type (or the VHDL
// compiler gets confused between signed/unsigned)
qualified_ = true;
return vhdl_expr::cast(to);
}
else else
return vhdl_expr::cast(to); return vhdl_expr::cast(to);
} }
void vhdl_const_bits::emit(std::ofstream &of, int level) const void vhdl_const_bits::emit(std::ofstream &of, int level) const
{ {
of << "signed'(\""; of << (qualified_ ? "signed'(\"" : "\"");
// The bits appear to be in reverse order // The bits appear to be in reverse order
std::string::const_reverse_iterator it; std::string::const_reverse_iterator it;
for (it = value_.rbegin(); it != value_.rend(); ++it) for (it = value_.rbegin(); it != value_.rend(); ++it)
of << vl_to_vhdl_bit(*it); of << vl_to_vhdl_bit(*it);
of << "\")"; of << (qualified_ ? "\")" : "\"");
} }
void vhdl_const_bit::emit(std::ofstream &of, int level) const void vhdl_const_bit::emit(std::ofstream &of, int level) const

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@ -132,6 +132,7 @@ public:
vhdl_expr *cast(const vhdl_type *to); vhdl_expr *cast(const vhdl_type *to);
private: private:
std::string value_; std::string value_;
bool qualified_;
}; };
class vhdl_const_bit : public vhdl_expr { class vhdl_const_bit : public vhdl_expr {