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Keep strings as strings in const ternary and concat

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This commit is contained in:
Clifford Wolf 2013-12-05 13:26:17 +01:00
parent e935bb6eda
commit 891e4b5b0d
3 changed files with 25 additions and 5 deletions
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14
frontends/ast/ast.cc
View file

@ -171,6 +171,7 @@ AstNode::AstNode(AstNodeType type, AstNode *child1, AstNode *child2)
is_output = false;
is_reg = false;
is_signed = false;
is_string = false;
range_valid = false;
port_id = 0;
range_left = -1;
@ -591,6 +592,8 @@ bool AstNode::operator==(const AstNode &other) const
return false;
if (is_signed != other.is_signed)
return false;
if (is_string != other.is_string)
return false;
if (range_valid != other.range_valid)
return false;
if (port_id != other.port_id)
@ -658,6 +661,14 @@ AstNode *AstNode::mkconst_bits(const std::vector<RTLIL::State> &v, bool is_signe
return node;
}
// create an AST node for a constant (using a string in bit vector form as value)
AstNode *AstNode::mkconst_str(const std::vector<RTLIL::State> &v)
{
AstNode *node = mkconst_str(RTLIL::Const(v).decode_string());
log_assert(node->bits == v);
return node;
}
// create an AST node for a constant (using a string as value)
AstNode *AstNode::mkconst_str(const std::string &str)
{
@ -671,6 +682,7 @@ AstNode *AstNode::mkconst_str(const std::string &str)
}
}
AstNode *node = AstNode::mkconst_bits(data, false);
node->is_string = true;
node->str = str;
return node;
}
@ -702,7 +714,7 @@ RTLIL::Const AstNode::asAttrConst()
RTLIL::Const val;
val.bits = bits;
if (!str.empty()) {
if (is_string) {
val.flags |= RTLIL::CONST_FLAG_STRING;
log_assert(val.decode_string() == str);
}

3
frontends/ast/ast.h
View file

@ -143,7 +143,7 @@ namespace AST
// node content - most of it is unused in most node types
std::string str;
std::vector<RTLIL::State> bits;
bool is_input, is_output, is_reg, is_signed, range_valid;
bool is_input, is_output, is_reg, is_signed, is_string, range_valid;
int port_id, range_left, range_right;
uint32_t integer;
@ -213,6 +213,7 @@ namespace AST
// helper functions for creating AST nodes for constants
static AstNode *mkconst_int(uint32_t v, bool is_signed, int width = 32);
static AstNode *mkconst_bits(const std::vector<RTLIL::State> &v, bool is_signed);
static AstNode *mkconst_str(const std::vector<RTLIL::State> &v);
static AstNode *mkconst_str(const std::string &str);
// helper function for creating sign-extended const objects

11
frontends/ast/simplify.cc
View file

@ -1176,6 +1176,7 @@ skip_dynamic_range_lvalue_expansion:;
// perform const folding when activated
if (const_fold && newNode == NULL)
{
bool string_op;
std::vector<RTLIL::State> tmp_bits;
RTLIL::Const (*const_func)(const RTLIL::Const&, const RTLIL::Const&, bool, bool, int);
RTLIL::Const dummy_arg;
@ -1306,6 +1307,9 @@ skip_dynamic_range_lvalue_expansion:;
choice = children[2];
if (choice != NULL && choice->type == AST_CONSTANT) {
RTLIL::Const y = choice->bitsAsConst(width_hint, sign_hint);
if (choice->is_string && y.bits.size() % 8 == 0 && sign_hint == false)
newNode = mkconst_str(y.bits);
else
newNode = mkconst_bits(y.bits, sign_hint);
} else if (children[1]->type == AST_CONSTANT && children[2]->type == AST_CONSTANT) {
RTLIL::Const a = children[1]->bitsAsConst(width_hint, sign_hint);
@ -1319,19 +1323,22 @@ skip_dynamic_range_lvalue_expansion:;
}
break;
case AST_CONCAT:
string_op = !children.empty();
for (auto it = children.begin(); it != children.end(); it++) {
if ((*it)->type != AST_CONSTANT)
goto not_const;
if (!(*it)->is_string)
string_op = false;
tmp_bits.insert(tmp_bits.end(), (*it)->bits.begin(), (*it)->bits.end());
}
newNode = mkconst_bits(tmp_bits, false);
newNode = string_op ? mkconst_str(tmp_bits) : mkconst_bits(tmp_bits, false);
break;
case AST_REPLICATE:
if (children.at(0)->type != AST_CONSTANT || children.at(1)->type != AST_CONSTANT)
goto not_const;
for (int i = 0; i < children[0]->bitsAsConst().as_int(); i++)
tmp_bits.insert(tmp_bits.end(), children.at(1)->bits.begin(), children.at(1)->bits.end());
newNode = mkconst_bits(tmp_bits, false);
newNode = children.at(1)->is_string ? mkconst_str(tmp_bits) : mkconst_bits(tmp_bits, false);
break;
default:
not_const: