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[smlnj] Diff of /sml/trunk/compiler/ElabData/prim/primop.sig
 [smlnj] / sml / trunk / compiler / ElabData / prim / primop.sig Diff of /sml/trunk/compiler/ElabData/prim/primop.sig

sml/trunk/src/compiler/FLINT/kernel/primop.sig revision 251, Mon Apr 19 02:55:26 1999 UTC sml/trunk/compiler/ElabData/prim/primop.sig revision 4992, Sat Apr 27 15:18:20 2019 UTC
# Line 1  Line 1
1  (* Copyright 1996 by AT&T Bell Laboratories *)  (* primop.sig
2  (* primop.sig *)   *
3     * COPYRIGHT (c) 2017 The Fellowship of SML/NJ (http://www.smlnj.org)
5                     Integer/Word Conversions Explained   *)

All integer/word conversion operations are expressed using five
primitive conversion operators. Algebraic equations over these
operators are easy to define and can be used to simplify composition
of conversion operations.

The five basic conversion operators are (in all cases, we assume
that (n >= m):

TEST(n,m)     -- map an n-bit, 2's complement signed value to an
m-bit, 2's complement signed value;
raise Overflow if the value is too large.

TESTU(n,m)    -- map an unsigned n-bit value to an m-bit 2's
complement value; raise Overflow if the value
is too large.

EXTEND(m,n)   -- sign extend an m-bit value to a n-bit value

TRUNC(n,m)    -- truncate an n-bit value to an m-bit value.

COPY(m,n)     -- copy an m-bit value to an n-bit value.

TEST, TESTU, and TRUNC are used to go from large values to small
ones, and EXTEND and COPY are used to go from small values to
large. The operators EXTEND, TRUNC, and COPY are "pure," while TEST
and TESTU may raise Overflow.

Conversions where the sizes are the same can be simplified to copies:

TEST(n,n)     == COPY(n,n)
EXTEND(n,n)   == COPY(n,n)    Note: this does not apply to TESTU
TRUNC(n,n)    == COPY(n,n)

The translation of conversion operations in the Word32 and Word8
structures (for example) is given by:

Module        function     => Implemented by
----------------------------------------------------------
Word32        toLargeInt    => TESTU(32,32)
toLargeIntX   => EXTEND(32,32)          = COPY(32,32)
fromLargeInt  => COPY(32,32)
toInt         => TESTU(32,31)
toIntX        => TEST(32,31)
fromInt       => EXTEND(31,32)
toLargeWord   => COPY(32,32)
toLargeWordX  => EXTEND(32,32)          = COPY(32,32)
fromLargeWord => TRUNC(32,32)           = COPY(32,32)

Word8         toLargeInt    => COPY(8,32)
toLargeIntX   => EXTEND(8,32)
fromLargeInt  => TRUNC(32,8)
toInt         => COPY(8,31)
toIntX        => EXTEND(8,31)
fromInt       => TRUNC(31,8)
toLargeWord   => COPY(8,32)
toLargeWordX  => EXTEND(8,32)
fromLargeWord => TRUNC(32,8)

Each operator composed with itself is itself, but with different parameters:

TEST(n,m) o TEST(p,n)         == TEST(p,m)
TESTU(n,m) o TESTU(p,n)       == TESTU(p,m)
EXTEND(n,m) o EXTEND(p,n)     == EXTEND(p,m)
TRUNC(n,m) o TRUNC(p,n)       == TRUNC(p,m)
COPY(n,m) o COPY(p,n)         == COPY(p,m)

The composition of these operators can be described by a simple algebra.

EXTEND(n,m) o COPY(p,n)       == COPY(p,m)   if (n > p)
== EXTEND(p,m) if (n = p)
COPY(n,m) o EXTEND(p,n)       == EXTEND(p,m) if (n = m)

TRUNC(n,m) o COPY(p,n)        == COPY(p,m)   if (m >= p)
== TRUNC(p,m)  if (m < p)

COPY(n,m) o TRUNC(p,n)        == TRUNC(p,m)  if (n = m)

TEST(n,m) o COPY(p,n)         == COPY(p,m)   if (m >= p)
== TEST(p,m)   if (m < p)

TESTU(n,m) o COPY(p,n)        == COPY(p,m)   if (m >= p)
== TESTU(p,m)  if (m < p)

COPY(n,m) o TEST(p,n)         == TEST(p,m)   if (n = m)

COPY(n,m) o TESTU(p,n)        == TESTU(p,m)  if (n = m)

TRUNC(n,m) o EXTEND(p,n)      == EXTEND(p,m) if (m >= p)
== TRUNC(p,m)  if (m < p)

TEST(n,m) o EXTEND(p,n)       == EXTEND(p,m) if (m >= p)
== TEST(p,m)   if (m < p)

TESTU(n,m) o EXTEND(p,n)      == EXTEND(p,m) if (m >= p)
== TESTU(p,m)  if (m < p)

For example, consider:
Word.toInt o Word.fromLargeWord o Word8.toLargeWord

This translates to:
TESTU(31,31) o TRUNC(32,31) o COPY(8,32)

and simplifies to:
TESTU(31,31) o COPY(8,31)

This further simplifies to:
COPY(8, 31)

Since both 8-bit and 31-bit quantities are tagged the same way, this
gets translated to a MOVE. With a smart register allocator that MOVE
can be eliminated.
*********************************************************************)
6
7  signature PRIM_OP =  signature PRIMOP =
8  sig  sig
9
10  (* numkind includes kind and number of bits *)  (* numkind includes kind and number of bits *)
# Line 126  Line 12
12    = INT of int    = INT of int
13    | UINT of int    | UINT of int
14    | FLOAT of int    | FLOAT of int
15    (* QUESTION: what about IntInf.int? *)
16
17  datatype arithop  datatype arithop
18    = + | - | * | / | ~           (* int or float *)        = ADD | SUB | MUL | NEG                   (* int or float *)
19    | ABS                         (* floating point only *)        | FDIV | FABS | FSQRT | FSIN | FCOS | FTAN (* floating point only *)
20    | LSHIFT | RSHIFT | RSHIFTL   (* int only *)    | LSHIFT | RSHIFT | RSHIFTL   (* int only *)
21    | ANDB | ORB | XORB | NOTB    (* int only *)    | ANDB | ORB | XORB | NOTB    (* int only *)
22          | DIV | MOD | QUOT | REM                  (* int only *)
23
24  datatype cmpop = > | >= | < | <= | LEU | LTU | GEU | GTU | EQL | NEQ      datatype cmpop
25          = GT | GTE | LT | LTE                     (* signed comparisons *)
26  (*        | LEU | LTU | GEU | GTU                   (* unsigned comparisons *)
27   * Various primitive operations.  Those that are designated "inline" are        | EQL | NEQ                               (* equality *)
28   * expanded into lambda code in terms of other operators,        | FSGN                                    (* floating point only *)
29   * as is the "checked=true" version of NUMSUBSCRIPT or NUMUPDATE.
30   * NUMSUBSCRIPT and NUMUPDATE are for arrays of floats or integers    (* datatype primop:
31   * stored WITHOUT boxing or tags.     * Various primitive operations. Those that are designated "inline" (L:) in
32       * the comments are expanded into lambda code in terms of other operators,
33       * as are the "checked=true" versions of NUMSUBSCRIPT and NUMUPDATE (L?:).
34       * "Environmental" primops (occurring in the InLine structure) are indicated
35       * by "E:" in the comment.
36       *
37       * See dev-notes/conversions.md for an explanation of the conversion operators.
38   *)   *)
39  datatype primop  datatype primop
40    = ARITH of {oper: arithop, overflow: bool, kind: numkind}        = ARITH of {                              (* E: arithmetic ops *)
41    | INLLSHIFT of numkind              oper: arithop, overflow: bool, kind: numkind
42    | INLRSHIFT of numkind            }
43    | INLRSHIFTL of numkind        | INLLSHIFT of numkind                    (* E: left shift *)
44    | CMP of {oper: cmpop, kind: numkind}        | INLRSHIFT of numkind                    (* E: right shift *)
45          | INLRSHIFTL of numkind                   (* E: right shift logical *)
46    | TESTU of int * int        | CMP of {oper: cmpop, kind: numkind}     (* E: generic compare *)
47    | TEST of int * int        | TESTU of int * int                      (* E: conversions to int, e.g. testu_31_31 *)
48    | TRUNC of int * int        | TEST of int * int                       (* E: conversions to int, e.g. test_32_31_w *)
49    | EXTEND of int * int        | TRUNC of int * int                      (* E: truncations to smaller int/word, e.g. trunc_32_31_i *)
50    | COPY of int * int        | EXTEND of int * int                     (* E: extensions to int32, word32 *)
51          | COPY of int * int                       (* E: conversions, e.g. copy_32_32_ii *)
52    | ROUND of {floor: bool, fromkind: numkind, tokind: numkind}        | TEST_INF of int                         (* E: intinf conversions, e.g. test_inf_31 *)
53    | REAL of {fromkind: numkind, tokind: numkind}        | TRUNC_INF of int                        (* E: intinf truncations, e.g. trunc_inf_31 *)
54          | EXTEND_INF of int                       (* E: intinf extensions, e.g. extend_8_inf *)
55    | NUMSUBSCRIPT of {kind: numkind, checked: bool, immutable: bool}        | COPY_INF of int                         (* E: conversions to intinf, e.g. copy_8_inf *)
56    | NUMUPDATE of {kind: numkind, checked: bool}        | ROUND of {                              (* E: floor, round *)
57                floor: bool, from: int, to: int
58    | SUBSCRIPT                  (* polymorphic array subscript *)            }
59    | SUBSCRIPTV                 (* poly vector subscript *)        | INT_TO_REAL of {                        (* E: real, real32 *)
60    | INLSUBSCRIPT               (* inline poly array subscript *)              from: int, to: int
61    | INLSUBSCRIPTV              (* inline poly vector subscript *)            }
62    | INLMKARRAY                 (* inline poly array creation *)        | NUMSUBSCRIPT of {                       (* E: L?: ordof, etc. *)
63                kind: numkind, checked: bool, immutable: bool
64    | PTREQL | PTRNEQ            (* pointer equality *)            }
65    | POLYEQL | POLYNEQ          (* polymorphic equality *)        | NUMUPDATE of {                          (* E: L?: store, etc. *)
66    | BOXED | UNBOXED            (* boxity tests *)              kind: numkind, checked: bool
67    | LENGTH                     (* vector, string, array, ... length *)            }
68    | OBJLENGTH                  (* length of arbitrary heap object *)        | SUBSCRIPT                               (* E: polymorphic array subscript *)
69    | CAST        | SUBSCRIPTV                              (* E: poly vector subscript *)
70    | WCAST        | INLSUBSCRIPT                            (* E: L: poly array subscript *)
71    | GETRUNVEC                  (* get the pointer to the run-vector *)        | INLSUBSCRIPTV                           (* E: L: poly vector subscript *)
72    | MARKEXN                    (* mark an exception value with a string *)        | INLMKARRAY                              (* E: L: poly array creation *)
73    | GETHDLR | SETHDLR          (* get/set exn handler pointer *)        | PTREQL | PTRNEQ                         (* E: pointer equality *)
74    | GETVAR | SETVAR            (* get/set var register *)        | POLYEQL | POLYNEQ                       (* E: polymorphic equality *)
75    | GETPSEUDO | SETPSEUDO      (* get/set pseudo registers *)        | BOXED | UNBOXED                         (* E: boxity tests *)
76    | SETMARK | DISPOSE          (* capture/dispose frames *)        | LENGTH                                  (* E: vector, string, array, ... length *)
77    | MAKEREF                    (* allocate a ref cell *)        | OBJLENGTH                               (* E: length of arbitrary heap object *)
78    | CALLCC | CAPTURE | THROW   (* continuation operations *)        | CAST                                    (* E: cast *)
79    | ISOLATE                    (* isolating a function *)        | GETHDLR | SETHDLR                       (* E: get/set exn handler pointer *)
80    | DEREF                      (* dereferencing *)        | GETVAR | SETVAR                         (* E: get/set var register *)
81    | ASSIGN                     (* assignment *)        | MAKEREF                                 (* E: allocate a ref cell *)
82          | CALLCC | CAPTURE | THROW                (* E: continuation operations *)
83          | ISOLATE                                 (* E: isolating a function *)
84          | DEREF                                   (* E: dereferencing *)
85          | ASSIGN                                  (* E: assignment *)
86          | UPDATE                                  (* E: array or reference update (maybe boxed) *)
87          | INLUPDATE                               (* E: L: array update (maybe boxed) *)
88          | UNBOXEDUPDATE                           (* E: update array of integers WITH tags
89                                                     * removed by Zhong, put back by Matthias
90                                                     * (see FLINT/trans/primopmap.sml) *)
91          | GETTAG                                  (* E: extract the tag portion of an
92                                                     * object's descriptor as an ML int *)
93          | MKSPECIAL                               (* E: make a special object *)
94          | SETSPECIAL                              (* E: set the state of a special object *)
95          | GETSPECIAL                              (* E: get the state of a special object *)
96          | INLMIN of numkind                       (* E: L: min *)
97          | INLMAX of numkind                       (* E: L: max *)
98          | INLABS of numkind                       (* E: L: abs *)
99          | INLNOT                                  (* E: L: bool not operator *)
100          | INLCOMPOSE                              (* E: L: compose "op o"  operator *)
101          | INLBEFORE                               (* E: L: "before" operator *)
102          | INLIGNORE                               (* E: L: "ignore" function *)
103        (* primops to support new array representations *)
104          | NEW_ARRAY0                              (* E: allocate zero-length array header *)
105          | GET_SEQ_DATA                            (* E: get data pointer from arr/vec header *)
106          | SUBSCRIPT_REC                           (* E: record subscript operation *)
107          | SUBSCRIPT_RAW64                         (* E: raw64 subscript operation *)
108          | INLIDENTITY                             (* E: polymorphic identity *)
109          | CVT64                                   (* E: convert between external and
110                                                     * internal representation of compiler
111                                                     * simulated 64-bit scalars, e.g. w64p *)
112        (* Primops to support C FFI. *)
113          | RAW_LOAD of numkind                     (* E: load from arbitrary memory location *)
114          | RAW_STORE of numkind                    (* E: store to arbitrary memory location *)
115        (* E: make a call to a C-function;
116         * The primop carries C function prototype information and specifies
117         * which of its (ML-) arguments are floating point. C prototype
118         * information is for use by the backend, ML information is for
119         * use by the CPS converter. *)
120          | RAW_CCALL of {
121                c_proto: PrimCTypes.c_proto,
122                ml_args: ccall_type list,
123                ml_res_opt: ccall_type option,
124                reentrant: bool
125              } option
126       (* Allocate uninitialized storage on the heap.
127        * The record is meant to hold short-lived C objects, i.e., they
128        * are not ML pointers.  The representation is
129        * the same as RECORD with tag tag_raw32 or tag_fblock.
130        *)
131          | RAW_RECORD of { fblock: bool }  (* E: *)
132
133        (* non-environmental primops (not found in InLine) *)
134    | UNBOXEDASSIGN              (* assignment to integer reference *)    | UNBOXEDASSIGN              (* assignment to integer reference *)
135    | UPDATE                     (* array update (maybe boxed) *)
136    | INLUPDATE                  (* inline array update (maybe boxed) *)        | WCAST                           (* ? *)
137    | BOXEDUPDATE                (* boxed array update *)        | MARKEXN                         (* mark an exception value with a string *)
138    | UNBOXEDUPDATE              (* update array of integers WITH tags *)
139          | INL_ARRAY                       (* L: polymorphic array allocation *)
140    | GETTAG                     (* extract the tag portion of an *)        | INL_VECTOR                      (* L: polymorphic vector allocation *)
141                                 (* object's descriptor as an ML int *)        | INL_MONOARRAY of numkind        (* L: monomorphic array allocation *)
142    | MKSPECIAL                  (* make a special object *)        | INL_MONOVECTOR of numkind       (* L: monomorphic vector allocation *)
| SETSPECIAL                 (* set the state of a special object *)
| GETSPECIAL                 (* get the state of a special object *)
| USELVAR | DEFLVAR
| INLDIV | INLMOD | INLREM   (* inline interger arithmetic *)
| INLMIN |INLMAX | INLABS    (* inline interger arithmetic *)
| INLNOT                     (* inline bool not operator *)
| INLCOMPOSE                 (* inline compose "op o"  operator *)
| INLBEFORE                  (* inline "before" operator *)
| INL_ARRAY                  (* inline polymorphic array allocation *)
| INL_VECTOR                 (* inline polymorphic vector allocation *)
| INL_MONOARRAY of numkind   (* inline monomorphic array allocation *)
| INL_MONOVECTOR of numkind  (* inline monomorphic vector allocation *)
143
144    | MKETAG                     (* make a new exception tag *)    | MKETAG                     (* make a new exception tag *)
145    | WRAP                       (* box a value by wrapping it *)    | WRAP                       (* box a value by wrapping it *)
146    | UNWRAP                     (* unbox a value by unwrapping it *)    | UNWRAP                     (* unbox a value by unwrapping it *)
(* Primops to support new array representations *)
| NEW_ARRAY0                  (* allocate zero-length array header *)
| GET_SEQ_DATA                (* get data pointer from arr/vec header *)
| SUBSCRIPT_REC               (* record subscript operation *)
| SUBSCRIPT_RAW64             (* raw64 subscript operation *)
147
148        and ccall_type =
149            CCI32 |                         (* passed as int32 *)
150            CCI64 |                         (* int64, currently unused *)
151            CCR64 |                         (* passed as real64 *)
152            CCML                            (* passed as Unsafe.Object.object *)
153
154  val IADD : primop  (* default integer addition *)  val IADD : primop  (* default integer addition *)
155  val ISUB : primop  (* default integer subtraction *)  val ISUB : primop  (* default integer subtraction *)
# Line 230  Line 164
164  val ILT : primop  val ILT : primop
165  val ILE : primop  val ILE : primop
166  val IGE : primop  val IGE : primop
167        val UIEQL : primop  (* for UINT kind, may not matter *)
168
169        val mkIEQL : int -> primop   (* make equality primop for other sizes *)
170        val mkUIEQL : int -> primop  (* and for unsigned (kind = UINT) *)
171
172  val prNumkind : numkind -> string  val prNumkind : numkind -> string
173  val prPrimop: primop -> string  val prPrimop: primop -> string
val purePrimop : primop -> bool
174  val mayRaise : primop -> bool  val mayRaise : primop -> bool
175
176  (* This should return more than just a boolean.  (* This should return more than just a boolean.
177   * True means "can not be dead-code eliminated" *)   * True means "can not be dead-code eliminated" *)
178  val effect : primop -> bool  val effect : primop -> bool

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