diff options
Diffstat (limited to 'gcc/ada/sem_eval.ads')
| -rw-r--r-- | gcc/ada/sem_eval.ads | 67 |
1 files changed, 58 insertions, 9 deletions
diff --git a/gcc/ada/sem_eval.ads b/gcc/ada/sem_eval.ads index 36553167b5e..02718850179 100644 --- a/gcc/ada/sem_eval.ads +++ b/gcc/ada/sem_eval.ads @@ -6,7 +6,7 @@ -- -- -- S p e c -- -- -- --- Copyright (C) 1992-2001 Free Software Foundation, Inc. -- +-- Copyright (C) 1992-2003 Free Software Foundation, Inc. -- -- -- -- GNAT is free software; you can redistribute it and/or modify it under -- -- terms of the GNU General Public License as published by the Free Soft- -- @@ -135,13 +135,29 @@ package Sem_Eval is type Compare_Result is (LT, LE, EQ, GT, GE, NE, Unknown); subtype Compare_GE is Compare_Result range EQ .. GE; subtype Compare_LE is Compare_Result range LT .. EQ; - function Compile_Time_Compare (L, R : Node_Id) return Compare_Result; + function Compile_Time_Compare + (L, R : Node_Id; + Rec : Boolean := False) + return Compare_Result; -- Given two expression nodes, finds out whether it can be determined -- at compile time how the runtime values will compare. An Unknown -- result means that the result of a comparison cannot be determined at -- compile time, otherwise the returned result indicates the known result -- of the comparison, given as tightly as possible (i.e. EQ or LT is a - -- preferred returned value to LE). + -- preferred returned value to LE). Rec is a parameter that is set True + -- for a recursive call from within Compile_Time_Compare to avoid some + -- infinite recursion cases. It should never be set by a client. + + procedure Flag_Non_Static_Expr (Msg : String; Expr : Node_Id); + -- This procedure is called after it has been determined that Expr is + -- not static when it is required to be. Msg is the text of a message + -- that explains the error. This procedure checks if an error is already + -- posted on Expr, if so, it does nothing unless All_Errors_Mode is set + -- in which case this flag is ignored. Otherwise the given message is + -- posted using Error_Msg_F, and then Why_Not_Static is called on + -- Expr to generate additional messages. The string given as Msg + -- should end with ! to make it an unconditional message, to ensure + -- that if it is posted, the entire set of messages is all posted. function Is_OK_Static_Expression (N : Node_Id) return Boolean; -- An OK static expression is one that is static in the RM definition @@ -275,24 +291,39 @@ package Sem_Eval is procedure Eval_Unary_Op (N : Node_Id); procedure Eval_Unchecked_Conversion (N : Node_Id); - procedure Fold_Str (N : Node_Id; Val : String_Id); + procedure Fold_Str (N : Node_Id; Val : String_Id; Static : Boolean); -- Rewrite N with a new N_String_Literal node as the result of the -- compile time evaluation of the node N. Val is the resulting string -- value from the folding operation. The Is_Static_Expression flag is -- set in the result node. The result is fully analyzed and resolved. + -- Static indicates whether the result should be considered static or + -- not (True = consider static). The point here is that normally all + -- string literals are static, but if this was the result of some + -- sequence of evaluation where values were known at compile time + -- but not static, then the result is not static. - procedure Fold_Uint (N : Node_Id; Val : Uint); + procedure Fold_Uint (N : Node_Id; Val : Uint; Static : Boolean); -- Rewrite N with a (N_Integer_Literal, N_Identifier, N_Character_Literal) -- node as the result of the compile time evaluation of the node N. Val -- is the result in the integer case and is the position of the literal -- in the literals list for the enumeration case. Is_Static_Expression -- is set True in the result node. The result is fully analyzed/resolved. + -- Static indicates whether the result should be considered static or + -- not (True = consider static). The point here is that normally all + -- string literals are static, but if this was the result of some + -- sequence of evaluation where values were known at compile time + -- but not static, then the result is not static. - procedure Fold_Ureal (N : Node_Id; Val : Ureal); + procedure Fold_Ureal (N : Node_Id; Val : Ureal; Static : Boolean); -- Rewrite N with a new N_Real_Literal node as the result of the compile -- time evaluation of the node N. Val is the resulting real value from -- the folding operation. The Is_Static_Expression flag is set in the - -- result node. The result is fully analyzed and result. + -- result node. The result is fully analyzed and result. Static + -- indicates whether the result should be considered static or not + -- (True = consider static). The point here is that normally all + -- string literals are static, but if this was the result of some + -- sequence of evaluation where values were known at compile time + -- but not static, then the result is not static. function Is_In_Range (N : Node_Id; @@ -330,7 +361,7 @@ package Sem_Eval is -- determined to be outside a compile_time known bound of Typ. A result -- of False does not mean that the expression is in range, merely that -- it cannot be determined at compile time that it is out of range. Flags - -- Int_Real and Fixed_Int are used like in routine Is_In_Range above. + -- Int_Real and Fixed_Int are used as in routine Is_In_Range above. function In_Subrange_Of (T1 : Entity_Id; @@ -341,7 +372,7 @@ package Sem_Eval is -- of values for scalar type T1 are always in the range of scalar type -- T2. A result of False does not mean that T1 is not in T2's subrange, -- only that it cannot be determined at compile time. Flag Fixed_Int is - -- used is like in routine Is_In_Range_Above. + -- used as in routine Is_In_Range above. function Is_Null_Range (Lo : Node_Id; Hi : Node_Id) return Boolean; -- Returns True if it can guarantee that Lo .. Hi is a null range. @@ -353,6 +384,24 @@ package Sem_Eval is -- If it cannot (because the value of Lo or Hi is not known at compile -- time) then it returns False. + procedure Why_Not_Static (Expr : Node_Id); + -- This procedure may be called after generating an error message that + -- complains that something is non-static. If it finds good reasons, + -- it generates one or more error messages pointing the appropriate + -- offending component of the expression. If no good reasons can be + -- figured out, then no messages are generated. The expectation here + -- is that the caller has already issued a message complaining that + -- the expression is non-static. Note that this message should be + -- placed using Error_Msg_F or Error_Msg_FE, so that it will sort + -- before any messages placed by this call. Note that it is fine to + -- call Why_Not_Static with something that is not an expression, and + -- usually this has no effect, but in some cases (N_Parameter_Association + -- or N_Range), it makes sense for the internal recursive calls. + + procedure Initialize; + -- Initializes the internal data structures. Must be called before + -- each separate main program unit (e.g. in a GNSA/ASIS context). + private -- The Eval routines are all marked inline, since they are called once |