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| author | Jannis Harder <me@jix.one> | 2023-03-20 12:50:14 +0100 |
|---|---|---|
| committer | Jannis Harder <me@jix.one> | 2023-03-20 12:52:46 +0100 |
| commit | fb1c2be76ba065a3da04f279b11e1ed2e59c75c5 (patch) | |
| tree | f452376b633c339d43d7e2e16cc991465ebeef25 /frontends | |
| parent | 61da330a38812a0a394131f9f434c736cb2239cf (diff) | |
| download | yosys-fb1c2be76ba065a3da04f279b11e1ed2e59c75c5.tar.gz yosys-fb1c2be76ba065a3da04f279b11e1ed2e59c75c5.tar.bz2 yosys-fb1c2be76ba065a3da04f279b11e1ed2e59c75c5.zip | |
verilog: Support void functions
The difference between void functions and tasks is that always_comb's
implicit sensitivity list behaves as if functions were inlined, but
ignores signals read only in tasks. This only matters for event based
simulation, and for synthesis we can treat a void function like a task.
Diffstat (limited to 'frontends')
| -rw-r--r-- | frontends/verilog/verilog_lexer.l | 1 | ||||
| -rw-r--r-- | frontends/verilog/verilog_parser.y | 19 |
2 files changed, 19 insertions, 1 deletions
diff --git a/frontends/verilog/verilog_lexer.l b/frontends/verilog/verilog_lexer.l index 958809319..249986668 100644 --- a/frontends/verilog/verilog_lexer.l +++ b/frontends/verilog/verilog_lexer.l @@ -276,6 +276,7 @@ TIME_SCALE_SUFFIX [munpf]?s "byte" { SV_KEYWORD(TOK_BYTE); } "shortint" { SV_KEYWORD(TOK_SHORTINT); } "longint" { SV_KEYWORD(TOK_LONGINT); } +"void" { SV_KEYWORD(TOK_VOID); } "eventually" { if (formal_mode) return TOK_EVENTUALLY; SV_KEYWORD(TOK_EVENTUALLY); } "s_eventually" { if (formal_mode) return TOK_EVENTUALLY; SV_KEYWORD(TOK_EVENTUALLY); } diff --git a/frontends/verilog/verilog_parser.y b/frontends/verilog/verilog_parser.y index 87b50438a..96413afb0 100644 --- a/frontends/verilog/verilog_parser.y +++ b/frontends/verilog/verilog_parser.y @@ -372,7 +372,7 @@ static void rewriteGenForDeclInit(AstNode *loop) %token TOK_POS_INDEXED TOK_NEG_INDEXED TOK_PROPERTY TOK_ENUM TOK_TYPEDEF %token TOK_RAND TOK_CONST TOK_CHECKER TOK_ENDCHECKER TOK_EVENTUALLY %token TOK_INCREMENT TOK_DECREMENT TOK_UNIQUE TOK_UNIQUE0 TOK_PRIORITY -%token TOK_STRUCT TOK_PACKED TOK_UNSIGNED TOK_INT TOK_BYTE TOK_SHORTINT TOK_LONGINT TOK_UNION +%token TOK_STRUCT TOK_PACKED TOK_UNSIGNED TOK_INT TOK_BYTE TOK_SHORTINT TOK_LONGINT TOK_VOID TOK_UNION %token TOK_BIT_OR_ASSIGN TOK_BIT_AND_ASSIGN TOK_BIT_XOR_ASSIGN TOK_ADD_ASSIGN %token TOK_SUB_ASSIGN TOK_DIV_ASSIGN TOK_MOD_ASSIGN TOK_MUL_ASSIGN %token TOK_SHL_ASSIGN TOK_SHR_ASSIGN TOK_SSHL_ASSIGN TOK_SSHR_ASSIGN @@ -1020,6 +1020,23 @@ task_func_decl: current_function_or_task = NULL; ast_stack.pop_back(); } | + attr TOK_FUNCTION opt_automatic TOK_VOID TOK_ID { + // The difference between void functions and tasks is that + // always_comb's implicit sensitivity list behaves as if functions were + // inlined, but ignores signals read only in tasks. This only matters + // for event based simulation, and for synthesis we can treat a void + // function like a task. + current_function_or_task = new AstNode(AST_TASK); + current_function_or_task->str = *$5; + append_attr(current_function_or_task, $1); + ast_stack.back()->children.push_back(current_function_or_task); + ast_stack.push_back(current_function_or_task); + current_function_or_task_port_id = 1; + delete $5; + } task_func_args_opt ';' task_func_body TOK_ENDFUNCTION { + current_function_or_task = NULL; + ast_stack.pop_back(); + } | attr TOK_FUNCTION opt_automatic func_return_type TOK_ID { current_function_or_task = new AstNode(AST_FUNCTION); current_function_or_task->str = *$5; |