mirrors/yosys
3
0
Fork 0
mirror of https://github.com/YosysHQ/yosys synced 2025-07-31 00:13:18 +00:00
Code Activity

Add LookaheadRewriter for proper bitselwrite support

Browse source 
Signed-off-by: Claire Wolf <claire@symbioticeda.com>
This commit is contained in:
Claire Wolf 2020-04-15 20:36:40 +02:00
parent 4711fea6c0
commit e1fb12a4b9
4 changed files with 144 additions and 4 deletions
Download patch file Download diff file Expand all files Collapse all files

8
frontends/ast/simplify.cc
View file

@ -1797,19 +1797,25 @@ bool AstNode::simplify(bool const_fold, bool at_zero, bool in_lvalue, int stage,
AstNode *ref_mask = new AstNode(AST_IDENTIFIER);
ref_mask->str = wire_mask->str;
ref_mask->id2ast = wire_mask;
ref_mask->was_checked = true;
AstNode *ref_data = new AstNode(AST_IDENTIFIER);
ref_data->str = wire_data->str;
ref_data->id2ast = wire_data;
ref_data->was_checked = true;
AstNode *old_data = lvalue->clone();
if (type == AST_ASSIGN_LE)
old_data->lookahead = true;
AstNode *shamt = shift_expr;
newNode->children.push_back(new AstNode(AST_ASSIGN_EQ, ref_mask->clone(),
new AstNode(AST_SHIFT_LEFT, mkconst_bits(std::vector<RTLIL::State>(result_width, State::S1), false), shamt->clone())));
newNode->children.push_back(new AstNode(AST_ASSIGN_EQ, ref_data->clone(),
new AstNode(AST_SHIFT_LEFT, new AstNode(AST_BIT_AND, mkconst_bits(std::vector<RTLIL::State>(result_width, State::S1), false), children[1]->clone()), shamt)));
newNode->children.push_back(new AstNode(type, lvalue, new AstNode(AST_BIT_OR, new AstNode(AST_BIT_AND, lvalue->clone(), new AstNode(AST_BIT_NOT, ref_mask)), ref_data)));
newNode->children.push_back(new AstNode(type, lvalue, new AstNode(AST_BIT_OR, new AstNode(AST_BIT_AND, old_data, new AstNode(AST_BIT_NOT, ref_mask)), ref_data)));
}
goto apply_newNode;