mirrors/yosys
3
0
Fork 0
mirror of https://github.com/YosysHQ/yosys synced 2025-06-06 06:03:23 +00:00
Code Activity

verilog: refactored constant function evaluation

Browse source 
Elaboration now attempts constant evaluation of any function call with
only constant arguments, regardless of the context or contents of the
function. This removes the concept of "recommended constant evaluation"
which previously applied to functions with `for` loops or which were
(sometimes erroneously) identified as recursive. Any function call in a
constant context (e.g., `localparam`) or which contains a constant-only
procedural construct (`while` or `repeat`) in its body will fail as
before if constant evaluation does not succeed.
This commit is contained in:
Zachary Snow 2021-01-27 13:21:13 -05:00
parent baf1875307
commit b93b6f4285
4 changed files with 176 additions and 72 deletions
Download patch file Download diff file Expand all files Collapse all files

7
frontends/ast/ast.h
View file

@ -264,10 +264,9 @@ namespace AST
// additional functionality for evaluating constant functions
struct varinfo_t { RTLIL::Const val; int offset; bool is_signed; };
bool has_const_only_constructs(bool &recommend_const_eval);
bool has_const_only_constructs(std::set<std::string>& visited, bool &recommend_const_eval);
void replace_variables(std::map<std::string, varinfo_t> &variables, AstNode *fcall);
AstNode *eval_const_function(AstNode *fcall);
bool has_const_only_constructs();
bool replace_variables(std::map<std::string, varinfo_t> &variables, AstNode *fcall, bool must_succeed);
AstNode *eval_const_function(AstNode *fcall, bool must_succeed);
bool is_simple_const_expr();
std::string process_format_str(const std::string &sformat, int next_arg, int stage, int width_hint, bool sign_hint);