diff options
Diffstat (limited to 'src/vhdl/parse.adb')
| -rw-r--r-- | src/vhdl/parse.adb | 247 |
1 files changed, 196 insertions, 51 deletions
diff --git a/src/vhdl/parse.adb b/src/vhdl/parse.adb index edcdb7a19..2991e07e3 100644 --- a/src/vhdl/parse.adb +++ b/src/vhdl/parse.adb @@ -4935,7 +4935,7 @@ package body Parse is -- precond : next token -- postcond: next token -- - -- [ §9.5 ] + -- [ LRM93 9.5 ] -- options ::= [ GUARDED ] [ delay_mechanism ] procedure Parse_Options (Stmt : Iir) is begin @@ -4947,26 +4947,75 @@ package body Parse is end Parse_Options; -- precond : next tkoen - -- postcond: ';' - -- - -- [ §9.5.1 ] - -- conditional_signal_assignment ::= - -- target <= options conditional_waveforms ; + -- postcond: next token (';') -- - -- [ §9.5.1 ] + -- [ LRM93 9.5.1 ] -- conditional_waveforms ::= -- { waveform WHEN condition ELSE } -- waveform [ WHEN condition ] - function Parse_Conditional_Signal_Assignment (Target: Iir) return Iir + function Parse_Conditional_Waveforms return Iir is - use Iir_Chains.Conditional_Waveform_Chain_Handling; - Res: Iir; - Cond_Wf, Last_Cond_Wf : Iir_Conditional_Waveform; + Wf : Iir; + Res : Iir; + Cond_Wf, N_Cond_Wf : Iir_Conditional_Waveform; begin - Res := Create_Iir (Iir_Kind_Concurrent_Conditional_Signal_Assignment); - Set_Target (Res, Target); - Location_Copy (Res, Get_Target (Res)); + Wf := Parse_Waveform; + if Current_Token /= Tok_When then + return Wf; + else + Res := Create_Iir (Iir_Kind_Conditional_Waveform); + Set_Location (Res); + Set_Waveform_Chain (Res, Wf); + + Cond_Wf := Res; + loop + -- Eat 'when' + Scan; + + Set_Condition (Cond_Wf, Parse_Expression); + + if Current_Token /= Tok_Else then + if Flags.Vhdl_Std = Vhdl_87 then + Error_Msg_Parse ("else missing in vhdl 87"); + end if; + exit; + end if; + + N_Cond_Wf := Create_Iir (Iir_Kind_Conditional_Waveform); + Set_Location (N_Cond_Wf); + Set_Chain (Cond_Wf, N_Cond_Wf); + Cond_Wf := N_Cond_Wf; + + -- Eat 'else' + Scan; + + Set_Waveform_Chain (Cond_Wf, Parse_Waveform); + + exit when Current_Token /= Tok_When; + end loop; + return Res; + end if; + end Parse_Conditional_Waveforms; + -- precond : '<=' (or ':=') + -- postcond: ';' + -- + -- [ LRM93 9.5.1 ] + -- concurrent_conditional_signal_assignment ::= + -- target <= [ GUARDED ] [ delay_mechanism ] conditional_waveforms ; + -- + -- [ LRM08 10.5.2.1 ] + -- concurrent_simple_waveform_assignment ::= + -- target <= [ GUARDED ] [ delay_mechanism ] waveform ; + function Parse_Concurrent_Conditional_Signal_Assignment (Target: Iir) + return Iir + is + Res: Iir; + Loc : Location_Type; + N_Res : Iir; + Wf : Iir; + begin + Loc := Get_Token_Location; case Current_Token is when Tok_Less_Equal => null; @@ -4976,30 +5025,34 @@ package body Parse is when others => Expect (Tok_Less_Equal); end case; + + -- Eat '<='. Scan; + -- Assume simple signal assignment. + Res := Create_Iir (Iir_Kind_Concurrent_Simple_Signal_Assignment); Parse_Options (Res); - Build_Init (Last_Cond_Wf); - loop - Cond_Wf := Create_Iir (Iir_Kind_Conditional_Waveform); - Append (Last_Cond_Wf, Res, Cond_Wf); - Set_Location (Cond_Wf); - Set_Waveform_Chain (Cond_Wf, Parse_Waveform); - exit when Current_Token /= Tok_When; - Scan; - Set_Condition (Cond_Wf, Parse_Expression); - if Current_Token /= Tok_Else then - if Flags.Vhdl_Std = Vhdl_87 then - Error_Msg_Parse ("else missing in vhdl 87"); - end if; - exit; + Wf := Parse_Conditional_Waveforms; + if Get_Kind (Wf) = Iir_Kind_Conditional_Waveform then + N_Res := + Create_Iir (Iir_Kind_Concurrent_Conditional_Signal_Assignment); + if Get_Guard (Res) /= Null_Iir then + Set_Guard (N_Res, N_Res); end if; - Scan; - end loop; + Set_Delay_Mechanism (N_Res, Get_Delay_Mechanism (Res)); + Set_Reject_Time_Expression (N_Res, Get_Reject_Time_Expression (Res)); + Free_Iir (Res); + Res := N_Res; + Set_Conditional_Waveform_Chain (Res, Wf); + else + Set_Waveform_Chain (Res, Wf); + end if; + Set_Location (Res, Loc); + Set_Target (Res, Target); Expect (Tok_Semi_Colon); return Res; - end Parse_Conditional_Signal_Assignment; + end Parse_Concurrent_Conditional_Signal_Assignment; -- precond : WITH -- postcond: ';' @@ -5336,53 +5389,145 @@ package body Parse is -- precond: '<=' -- postcond: next token -- - -- [ §8.4 ] + -- [ LRM93 8.4 ] -- signal_assignment_statement ::= -- [ label : ] target <= [ delay_mechanism ] waveform ; + -- + -- [ LRM08 10.5 Signal assignment statement ] + -- signal_assignement_statement ::= + -- [ label : ] simple_signal_assignement + -- | [ label : ] conditional_signal_assignement + -- | [ label : ] selected_signal_assignement (TODO) function Parse_Signal_Assignment_Statement (Target : Iir) return Iir is Stmt : Iir; - Wave_Chain : Iir_Waveform_Element; + N_Stmt : Iir; + Wave_Chain : Iir; begin - Stmt := Create_Iir (Iir_Kind_Signal_Assignment_Statement); - Location_Copy (Stmt, Target); + Stmt := Create_Iir (Iir_Kind_Simple_Signal_Assignment_Statement); + Set_Location (Stmt); Set_Target (Stmt, Target); + + -- Eat '<='. Scan; + Parse_Delay_Mechanism (Stmt); - Wave_Chain := Parse_Waveform; + + Wave_Chain := Parse_Conditional_Waveforms; + -- LRM 8.4 Signal assignment statement -- It is an error is the reserved word UNAFFECTED appears as a - -- waveform in a (sequential) signa assignment statement. + -- waveform in a (sequential) signal assignment statement. if Wave_Chain = Null_Iir then Error_Msg_Parse ("'unaffected' is not allowed in a sequential statement"); + elsif Get_Kind (Wave_Chain) = Iir_Kind_Conditional_Waveform then + if Flags.Vhdl_Std < Vhdl_08 then + Error_Msg_Parse + ("conditional signal assignment not allowed in before vhdl08"); + end if; + N_Stmt := + Create_Iir (Iir_Kind_Conditional_Signal_Assignment_Statement); + Location_Copy (N_Stmt, Stmt); + Set_Target (N_Stmt, Target); + Set_Delay_Mechanism (N_Stmt, Get_Delay_Mechanism (Stmt)); + Set_Reject_Time_Expression + (N_Stmt, Get_Reject_Time_Expression (Stmt)); + Set_Conditional_Waveform_Chain (N_Stmt, Wave_Chain); + Free_Iir (Stmt); + Stmt := N_Stmt; + else + Set_Waveform_Chain (Stmt, Wave_Chain); end if; - Set_Waveform_Chain (Stmt, Wave_Chain); + return Stmt; end Parse_Signal_Assignment_Statement; + -- precond: WHEN + -- postcond: next token + -- + -- [ LRM08 10.5.3 Conditional signal assignments ] + -- conditional_expressions ::= + -- expression WHEN condition + -- { ELSE expression WHEN condition } + -- [ ELSE expression ] + function Parse_Conditional_Expression (Expr : Iir) return Iir + is + Res : Iir; + El, N_El : Iir; + begin + Res := Create_Iir (Iir_Kind_Conditional_Expression); + Set_Location (Res); + Set_Expression (Res, Expr); + El := Res; + + loop + -- Eat 'when' + Scan; + + Set_Condition (El, Parse_Expression); + + exit when Current_Token /= Tok_Else; + + N_El := Create_Iir (Iir_Kind_Conditional_Expression); + Set_Location (N_El); + Set_Chain (El, N_El); + El := N_El; + + -- Eat 'else' + Scan; + + Set_Expression (N_El, Parse_Expression); + + exit when Current_Token /= Tok_When; + end loop; + + return Res; + end Parse_Conditional_Expression; + -- precond: ':=' -- postcond: next token -- - -- [ §8.5 ] + -- [ LRM93 8.5 ] -- variable_assignment_statement ::= -- [ label : ] target := expression ; function Parse_Variable_Assignment_Statement (Target : Iir) return Iir is Stmt : Iir; + Loc : Location_Type; + Expr : Iir; begin - Stmt := Create_Iir (Iir_Kind_Variable_Assignment_Statement); - Location_Copy (Stmt, Target); - Set_Target (Stmt, Target); + Loc := Get_Token_Location; + + -- Eat ':=' Scan; - Set_Expression (Stmt, Parse_Expression); + + Expr := Parse_Expression; + + if Current_Token = Tok_When then + if Flags.Vhdl_Std < Vhdl_08 then + Error_Msg_Parse + ("conditional variable assignment not allowed before vhdl08"); + end if; + Stmt := + Create_Iir (Iir_Kind_Conditional_Variable_Assignment_Statement); + Set_Location (Stmt, Loc); + Set_Target (Stmt, Target); + Set_Conditional_Expression + (Stmt, Parse_Conditional_Expression (Expr)); + else + Stmt := Create_Iir (Iir_Kind_Variable_Assignment_Statement); + Set_Location (Stmt, Loc); + Set_Target (Stmt, Target); + Set_Expression (Stmt, Expr); + end if; return Stmt; end Parse_Variable_Assignment_Statement; -- precond: next token -- postcond: next token -- - -- [ 8 ] + -- [ LRM93 8 ] -- sequence_of_statement ::= { sequential_statement } -- -- [ 8 ] @@ -6641,7 +6786,7 @@ package body Parse is -- precond : first token -- postcond: END -- - -- [ §9 ] + -- [ LRM93 9 ] -- concurrent_statement ::= block_statement -- | process_statement -- | concurrent_procedure_call_statement @@ -6650,15 +6795,15 @@ package body Parse is -- | component_instantiation_statement -- | generate_statement -- - -- [ §9.4 ] + -- [ LRM93 9.4 ] -- concurrent_assertion_statement ::= -- [ label : ] [ POSTPONED ] assertion ; -- - -- [ §9.3 ] + -- [ LRM93 9.3 ] -- concurrent_procedure_call_statement ::= -- [ label : ] [ POSTPONED ] procedure_call ; -- - -- [ §9.5 ] + -- [ LRM93 9.5 ] -- concurrent_signal_assignment_statement ::= -- [ label : ] [ POSTPONED ] conditional_signal_assignment -- | [ label : ] [ POSTPONED ] selected_signal_assignment @@ -6671,7 +6816,7 @@ package body Parse is | Tok_Assign => -- This is a conditional signal assignment. -- Error for ':=' is handled by the subprogram. - return Parse_Conditional_Signal_Assignment (Target); + return Parse_Concurrent_Conditional_Signal_Assignment (Target); when Tok_Semi_Colon => -- a procedure call or a component instantiation. -- Parse it as a procedure call, may be revert to a @@ -6698,7 +6843,7 @@ package body Parse is Expect (Tok_Semi_Colon); return Res; else - return Parse_Conditional_Signal_Assignment + return Parse_Concurrent_Conditional_Signal_Assignment (Parse_Simple_Expression (Target)); end if; end case; @@ -6878,7 +7023,7 @@ package body Parse is Id := Parse_Aggregate; if Current_Token = Tok_Less_Equal then -- This is a conditional signal assignment. - Stmt := Parse_Conditional_Signal_Assignment (Id); + Stmt := Parse_Concurrent_Conditional_Signal_Assignment (Id); else Error_Msg_Parse ("'<=' expected after aggregate"); Eat_Tokens_Until_Semi_Colon; |