2018-08-11 23:12:45 +06:00

1822 lines
53 KiB
C

/* Pawn compiler - Staging buffer and optimizer
*
* The staging buffer
* ------------------
* The staging buffer allows buffered output of generated code, deletion
* of redundant code, optimization by a tinkering process and reversing
* the ouput of evaluated expressions (which is used for the reversed
* evaluation of arguments in functions).
* Initially, stgwrite() writes to the file directly, but after a call to
* stgset(TRUE), output is redirected to the buffer. After a call to
* stgset(FALSE), stgwrite()'s output is directed to the file again. Thus
* only one routine is used for writing to the output, which can be
* buffered output or direct output.
*
* staging buffer variables: stgbuf - the buffer
* stgidx - current index in the staging buffer
* staging - if true, write to the staging buffer;
* if false, write to file directly.
*
* The peephole optimizer uses a dual "pipeline". The staging buffer (described
* above) gets optimized for each expression or sub-expression in a function
* call. The peephole optimizer is recursive, but it does not span multiple
* sub-expressions. However, the data gets written to a second buffer that
* behaves much like the staging buffer. This second buffer gathers all
* optimized strings from the staging buffer for a complete expression. The
* peephole optmizer then runs over this second buffer to find optimzations
* across function parameter boundaries.
*
*
* Copyright (c) ITB CompuPhase, 1997-2006
*
* This software is provided "as-is", without any express or implied warranty.
* In no event will the authors be held liable for any damages arising from
* the use of this software.
*
* Permission is granted to anyone to use this software for any purpose,
* including commercial applications, and to alter it and redistribute it
* freely, subject to the following restrictions:
*
* 1. The origin of this software must not be misrepresented; you must not
* claim that you wrote the original software. If you use this software in
* a product, an acknowledgment in the product documentation would be
* appreciated but is not required.
* 2. Altered source versions must be plainly marked as such, and must not be
* misrepresented as being the original software.
* 3. This notice may not be removed or altered from any source distribution.
*
* Version: $Id: sc7.c 3579 2006-06-06 13:35:29Z thiadmer $
*/
#include <assert.h>
#include <stdio.h>
#include <stdlib.h> /* for atoi() */
#include <string.h>
#include <ctype.h>
#if defined FORTIFY
#include <alloc/fortify.h>
#endif
#include "sc.h"
#define seqsize(o,p) (opcodes(o)+opargs(p))
typedef struct {
char *find;
char *replace;
int savesize; /* number of bytes saved (in bytecode) */
} SEQUENCE;
static SEQUENCE sequences[] = {
/* A very common sequence in four varieties
* load.s.pri n1 load.s.pri n2
* push.pri load.s.alt n1
* load.s.pri n2 -
* pop.alt -
* --------------------------------------
* load.pri n1 load.s.pri n2
* push.pri load.alt n1
* load.s.pri n2 -
* pop.alt -
* --------------------------------------
* load.s.pri n1 load.pri n2
* push.pri load.s.alt n1
* load.pri n2 -
* pop.alt -
* --------------------------------------
* load.pri n1 load.pri n2
* push.pri load.alt n1
* load.pri n2 -
* pop.alt -
*/
{
"load.s.pri %1!push.pri!load.s.pri %2!pop.alt!",
"load.s.pri %2!load.s.alt %1!",
seqsize(4,2) - seqsize(2,2)
},
{
"load.pri %1!push.pri!load.s.pri %2!pop.alt!",
"load.s.pri %2!load.alt %1!",
seqsize(4,2) - seqsize(2,2)
},
{
"load.s.pri %1!push.pri!load.pri %2!pop.alt!",
"load.pri %2!load.s.alt %1!",
seqsize(4,2) - seqsize(2,2)
},
{
"load.pri %1!push.pri!load.pri %2!pop.alt!",
"load.pri %2!load.alt %1!",
seqsize(4,2) - seqsize(2,2)
},
/* (#1#) The above also occurs with "addr.pri" (array
* indexing) as the first line; so that adds 2 cases.
*/
{
"addr.pri %1!push.pri!load.s.pri %2!pop.alt!",
"addr.alt %1!load.s.pri %2!",
seqsize(4,2) - seqsize(2,2)
},
{
"addr.pri %1!push.pri!load.pri %2!pop.alt!",
"addr.alt %1!load.pri %2!",
seqsize(4,2) - seqsize(2,2)
},
/* And the same sequence with const.pri as either the first
* or the second load instruction: four more cases.
*/
{
"const.pri %1!push.pri!load.s.pri %2!pop.alt!",
"load.s.pri %2!const.alt %1!",
seqsize(4,2) - seqsize(2,2)
},
{
"const.pri %1!push.pri!load.pri %2!pop.alt!",
"load.pri %2!const.alt %1!",
seqsize(4,2) - seqsize(2,2)
},
{
"load.s.pri %1!push.pri!const.pri %2!pop.alt!",
"const.pri %2!load.s.alt %1!",
seqsize(4,2) - seqsize(2,2)
},
{
"load.pri %1!push.pri!const.pri %2!pop.alt!",
"const.pri %2!load.alt %1!",
seqsize(4,2) - seqsize(2,2)
},
/* The same as above, but now with "addr.pri" (array
* indexing) on the first line and const.pri on
* the second.
*/
{
"addr.pri %1!push.pri!const.pri %2!pop.alt!",
"addr.alt %1!const.pri %2!",
seqsize(4,2) - seqsize(2,2)
},
{
"addr.pri %1!push.pri!zero.pri!pop.alt!",
"addr.alt %1!zero.pri!",
seqsize(4,1) - seqsize(2,1)
},
/* ??? add references */
/* Chained relational operators can contain sequences like:
* move.pri load.s.pri n1
* push.pri -
* load.s.pri n1 -
* pop.alt -
* The above also accurs for "load.pri" and for "const.pri",
* so add another two cases.
*/
{
"move.pri!push.pri!load.s.pri %1!pop.alt!",
"load.s.pri %1!",
seqsize(4,1) - seqsize(1,1)
},
{
"move.pri!push.pri!load.pri %1!pop.alt!",
"load.pri %1!",
seqsize(4,1) - seqsize(1,1)
},
{
"move.pri!push.pri!const.pri %1!pop.alt!",
"const.pri %1!",
seqsize(4,1) - seqsize(1,1)
},
/* More optimizations for chained relational operators; the
* continuation sequences can be simplified if they turn out
* to be termination sequences:
* xchg sless also for sless, sgeq and sleq
* sgrtr pop.alt
* swap.alt and
* and ;$exp
* pop.alt -
* ;$exp -
* --------------------------------------
* xchg sless also for sless, sgeq and sleq
* sgrtr pop.alt
* swap.alt and
* and jzer n1
* pop.alt -
* jzer n1 -
* --------------------------------------
* xchg jsgeq n1 also for sless, sgeq and sleq
* sgrtr ;$exp (occurs for non-chained comparisons)
* jzer n1 -
* ;$exp -
* --------------------------------------
* xchg sless also for sless, sgeq and sleq
* sgrtr ;$exp (occurs for non-chained comparisons)
* ;$exp -
*/
{
"xchg!sgrtr!swap.alt!and!pop.alt!;$exp!",
"sless!pop.alt!and!;$exp!",
seqsize(5,0) - seqsize(3,0)
},
{
"xchg!sless!swap.alt!and!pop.alt!;$exp!",
"sgrtr!pop.alt!and!;$exp!",
seqsize(5,0) - seqsize(3,0)
},
{
"xchg!sgeq!swap.alt!and!pop.alt!;$exp!",
"sleq!pop.alt!and!;$exp!",
seqsize(5,0) - seqsize(3,0)
},
{
"xchg!sleq!swap.alt!and!pop.alt!;$exp!",
"sgeq!pop.alt!and!;$exp!",
seqsize(5,0) - seqsize(3,0)
},
{
"xchg!sgrtr!swap.alt!and!pop.alt!jzer %1!",
"sless!pop.alt!and!jzer %1!",
seqsize(5,0) - seqsize(3,0)
},
{
"xchg!sless!swap.alt!and!pop.alt!jzer %1!",
"sgrtr!pop.alt!and!jzer %1!",
seqsize(5,0) - seqsize(3,0)
},
{
"xchg!sgeq!swap.alt!and!pop.alt!jzer %1!",
"sleq!pop.alt!and!jzer %1!",
seqsize(5,0) - seqsize(3,0)
},
{
"xchg!sleq!swap.alt!and!pop.alt!jzer %1!",
"sgeq!pop.alt!and!jzer %1!",
seqsize(5,0) - seqsize(3,0)
},
{
"xchg!sgrtr!jzer %1!;$exp!",
"jsgeq %1!;$exp!",
seqsize(3,1) - seqsize(1,1)
},
{
"xchg!sless!jzer %1!;$exp!",
"jsleq %1!;$exp!",
seqsize(3,1) - seqsize(1,1)
},
{
"xchg!sgeq!jzer %1!;$exp!",
"jsgrtr %1!;$exp!",
seqsize(3,1) - seqsize(1,1)
},
{
"xchg!sleq!jzer %1!;$exp!",
"jsless %1!;$exp!",
seqsize(3,1) - seqsize(1,1)
},
{
"xchg!sgrtr!;$exp!",
"sless!;$exp!",
seqsize(2,0) - seqsize(1,0)
},
{
"xchg!sless!;$exp!",
"sgrtr!;$exp!",
seqsize(2,0) - seqsize(1,0)
},
{
"xchg!sgeq!;$exp!",
"sleq!;$exp!",
seqsize(2,0) - seqsize(1,0)
},
{
"xchg!sleq!;$exp!",
"sgeq!;$exp!",
seqsize(2,0) - seqsize(1,0)
},
/* The entry to chained operators is also opt to optimization
* load.s.pri n1 load.s.pri n2
* load.s.alt n2 load.s.alt n1
* xchg -
* --------------------------------------
* load.s.pri n1 load.pri n2
* load.alt n2 load.s.alt n1
* xchg -
* --------------------------------------
* load.s.pri n1 const.pri n2
* const.alt n2 load.s.alt n1
* xchg -
* --------------------------------------
* and all permutations...
*/
{
"load.s.pri %1!load.s.alt %2!xchg!",
"load.s.pri %2!load.s.alt %1!",
seqsize(3,2) - seqsize(2,2)
},
{
"load.s.pri %1!load.alt %2!xchg!",
"load.pri %2!load.s.alt %1!",
seqsize(3,2) - seqsize(2,2)
},
{
"load.s.pri %1!const.alt %2!xchg!",
"const.pri %2!load.s.alt %1!",
seqsize(3,2) - seqsize(2,2)
},
{
"load.pri %1!load.s.alt %2!xchg!",
"load.s.pri %2!load.alt %1!",
seqsize(3,2) - seqsize(2,2)
},
{
"load.pri %1!load.alt %2!xchg!",
"load.pri %2!load.alt %1!",
seqsize(3,2) - seqsize(2,2)
},
{
"load.pri %1!const.alt %2!xchg!",
"const.pri %2!load.alt %1!",
seqsize(3,2) - seqsize(2,2)
},
{
"const.pri %1!load.s.alt %2!xchg!",
"load.s.pri %2!const.alt %1!",
seqsize(3,2) - seqsize(2,2)
},
{
"const.pri %1!load.alt %2!xchg!",
"load.pri %2!const.alt %1!",
seqsize(3,2) - seqsize(2,2)
},
/* some sequences where PRI is moved to ALT can be optimized
* further when considering what follows
* move.alt const.alt n1
* const.pri %1 -
* xchg -
* (also for load.s.pri and load.pri)
* --------------------------------------
* lref.pri %1 lref.alt %1
* move.alt [load.pri %2]
* [load.pri %2] -
* (where [load.pri %2] may also be another operatrion loading PRI)
*/
{
"move.alt!const.pri %1!xchg!",
"const.alt %1!",
seqsize(3,1) - seqsize(1,1)
},
{
"move.alt!load.pri %1!xchg!",
"load.alt %1!",
seqsize(3,1) - seqsize(1,1)
},
{
"move.alt!load.s.pri %1!xchg!",
"load.s.alt %1!",
seqsize(3,1) - seqsize(1,1)
},
/* ----- */
{
"lref.pri %1!move.alt!load.pri %2!",
"lref.alt %1!load.pri %2!",
seqsize(3,2) - seqsize(2,2)
},
{
"lref.pri %1!move.alt!load.s.pri %2!",
"lref.alt %1!load.s.pri %2!",
seqsize(3,2) - seqsize(2,2)
},
{
"lref.pri %1!move.alt!const.pri %2!",
"lref.alt %1!const.pri %2!",
seqsize(3,2) - seqsize(2,2)
},
{
"lref.s.pri %1!move.alt!load.pri %2!",
"lref.s.alt %1!load.pri %2!",
seqsize(3,2) - seqsize(2,2)
},
{
"lref.s.pri %1!move.alt!load.s.pri %2!",
"lref.s.alt %1!load.s.pri %2!",
seqsize(3,2) - seqsize(2,2)
},
{
"lref.s.pri %1!move.alt!const.pri %2!",
"lref.s.alt %1!const.pri %2!",
seqsize(3,2) - seqsize(2,2)
},
/* Array indexing can merit from special instructions.
* Simple indexed array lookup can be optimized quite
* a bit.
* addr.pri n1 addr.alt n1
* push.pri load.s.pri n2
* load.s.pri n2 bounds n3
* bounds n3 lidx.b n4
* shl.c.pri n4 -
* pop.alt -
* add -
* load.i -
*
* And to prepare for storing a value in an array
* addr.pri n1 addr.alt n1
* push.pri load.s.pri n2
* load.s.pri n2 bounds n3
* bounds n3 idxaddr.b n4
* shl.c.pri n4 -
* pop.alt -
* add -
*
* Notes (additional cases):
* 1. instruction addr.pri can also be const.pri (for
* global arrays)
* 2. the bounds instruction can be absent
* 3. when "n4" (the shift value) is the 2 (with 32-bit cells), use the
* even more optimal instructions LIDX and IDDXADDR
*
* If the array index is more complex, one can only optimize
* the last four instructions:
* shl.c.pri n1 pop.alt
* pop.alt lidx.b n1
* add -
* loadi -
* --------------------------------------
* shl.c.pri n1 pop.alt
* pop.alt idxaddr.b n1
* add -
*/
#if !defined BIT16
/* loading from array, "cell" shifted */
{
"addr.pri %1!push.pri!load.s.pri %2!bounds %3!shl.c.pri 2!pop.alt!add!load.i!",
"addr.alt %1!load.s.pri %2!bounds %3!lidx!",
seqsize(8,4) - seqsize(4,3)
},
{
"const.pri %1!push.pri!load.s.pri %2!bounds %3!shl.c.pri 2!pop.alt!add!load.i!",
"const.alt %1!load.s.pri %2!bounds %3!lidx!",
seqsize(8,4) - seqsize(4,3)
},
{
"addr.pri %1!push.pri!load.s.pri %2!shl.c.pri 2!pop.alt!add!load.i!",
"addr.alt %1!load.s.pri %2!lidx!",
seqsize(7,3) - seqsize(3,2)
},
{
"const.pri %1!push.pri!load.s.pri %2!shl.c.pri 2!pop.alt!add!load.i!",
"const.alt %1!load.s.pri %2!lidx!",
seqsize(7,3) - seqsize(3,2)
},
#endif
/* loading from array, not "cell" shifted */
{
"addr.pri %1!push.pri!load.s.pri %2!bounds %3!shl.c.pri %4!pop.alt!add!load.i!",
"addr.alt %1!load.s.pri %2!bounds %3!lidx.b %4!",
seqsize(8,4) - seqsize(4,4)
},
{
"const.pri %1!push.pri!load.s.pri %2!bounds %3!shl.c.pri %4!pop.alt!add!load.i!",
"const.alt %1!load.s.pri %2!bounds %3!lidx.b %4!",
seqsize(8,4) - seqsize(4,4)
},
{
"addr.pri %1!push.pri!load.s.pri %2!shl.c.pri %3!pop.alt!add!load.i!",
"addr.alt %1!load.s.pri %2!lidx.b %3!",
seqsize(7,3) - seqsize(3,3)
},
{
"const.pri %1!push.pri!load.s.pri %2!shl.c.pri %3!pop.alt!add!load.i!",
"const.alt %1!load.s.pri %2!lidx.b %3!",
seqsize(7,3) - seqsize(3,3)
},
#if !defined BIT16
/* array index calculation for storing a value, "cell" aligned */
{
"addr.pri %1!push.pri!load.s.pri %2!bounds %3!shl.c.pri 2!pop.alt!add!",
"addr.alt %1!load.s.pri %2!bounds %3!idxaddr!",
seqsize(7,4) - seqsize(4,3)
},
{
"const.pri %1!push.pri!load.s.pri %2!bounds %3!shl.c.pri 2!pop.alt!add!",
"const.alt %1!load.s.pri %2!bounds %3!idxaddr!",
seqsize(7,4) - seqsize(4,3)
},
{
"addr.pri %1!push.pri!load.s.pri %2!shl.c.pri 2!pop.alt!add!",
"addr.alt %1!load.s.pri %2!idxaddr!",
seqsize(6,3) - seqsize(3,2)
},
{
"const.pri %1!push.pri!load.s.pri %2!shl.c.pri 2!pop.alt!add!",
"const.alt %1!load.s.pri %2!idxaddr!",
seqsize(6,3) - seqsize(3,2)
},
#endif
/* array index calculation for storing a value, not "cell" packed */
{
"addr.pri %1!push.pri!load.s.pri %2!bounds %3!shl.c.pri %4!pop.alt!add!",
"addr.alt %1!load.s.pri %2!bounds %3!idxaddr.b %4!",
seqsize(7,4) - seqsize(4,4)
},
{
"const.pri %1!push.pri!load.s.pri %2!bounds %3!shl.c.pri %4!pop.alt!add!",
"const.alt %1!load.s.pri %2!bounds %3!idxaddr.b %4!",
seqsize(7,4) - seqsize(4,4)
},
{
"addr.pri %1!push.pri!load.s.pri %2!shl.c.pri %3!pop.alt!add!",
"addr.alt %1!load.s.pri %2!idxaddr.b %3!",
seqsize(6,3) - seqsize(3,3)
},
{
"const.pri %1!push.pri!load.s.pri %2!shl.c.pri %3!pop.alt!add!",
"const.alt %1!load.s.pri %2!idxaddr.b %3!",
seqsize(6,3) - seqsize(3,3)
},
#if !defined BIT16
/* the shorter array indexing sequences, see above for comments */
{
"shl.c.pri 2!pop.alt!add!loadi!",
"pop.alt!lidx!",
seqsize(4,1) - seqsize(2,0)
},
{
"shl.c.pri 2!pop.alt!add!",
"pop.alt!idxaddr!",
seqsize(3,1) - seqsize(2,0)
},
#endif
{
"shl.c.pri %1!pop.alt!add!loadi!",
"pop.alt!lidx.b %1!",
seqsize(4,1) - seqsize(2,1)
},
{
"shl.c.pri %1!pop.alt!add!",
"pop.alt!idxaddr.b %1!",
seqsize(3,1) - seqsize(2,1)
},
/* For packed arrays, there is another case (packed arrays
* do not take advantage of the LIDX or IDXADDR instructions).
* addr.pri n1 addr.alt n1
* push.pri load.s.pri n2
* load.s.pri n2 bounds n3
* bounds n3 -
* pop.alt -
*
* Notes (additional cases):
* 1. instruction addr.pri can also be const.pri (for
* global arrays)
* 2. the bounds instruction can be absent, but that
* case is already handled (see #1#)
*/
{
"addr.pri %1!push.pri!load.s.pri %2!bounds %3!pop.alt!",
"addr.alt %1!load.s.pri %2!bounds %3!",
seqsize(5,3) - seqsize(3,3)
},
{
"const.pri %1!push.pri!load.s.pri %2!bounds %3!pop.alt!",
"const.alt %1!load.s.pri %2!bounds %3!",
seqsize(5,3) - seqsize(3,3)
},
/* Declaration of simple variables often follows the sequence:
* ;$lcl <name> <stk> ;$lcl <name> <stk>
* stack -4 push.c <constval>
* const.pri <constval> ;$exp
* stor.s.pri <stk> -
* ;$exp -
*/
{
";$lcl %1 %2!stack -4!const.pri %3!stor.s.pri %2!;$exp!",
";$lcl %1 %2!push.c %3!;$exp!",
seqsize(3,3) - seqsize(1,1)
},
{
";$lcl %1 %2!stack -4!zero.pri!stor.s.pri %2!;$exp!",
";$lcl %1 %2!push.c 0!;$exp!",
seqsize(3,2) - seqsize(1,1)
},
/* During a calculation, the intermediate result must sometimes
* be moved from PRI to ALT, like in:
* push.pri move.alt
* load.s.pri n1 load.s.pri n1
* pop.alt -
*
* The above also accurs for "load.pri" and for "const.pri",
* so add another two cases.
*/
{
"push.pri!load.s.pri %1!pop.alt!",
"move.alt!load.s.pri %1!",
seqsize(3,1) - seqsize(2,1)
},
{
"push.pri!load.pri %1!pop.alt!",
"move.alt!load.pri %1!",
seqsize(3,1) - seqsize(2,1)
},
{
"push.pri!const.pri %1!pop.alt!",
"move.alt!const.pri %1!",
seqsize(3,1) - seqsize(2,1)
},
{
"push.pri!zero.pri!pop.alt!",
"move.alt!zero.pri!",
seqsize(3,0) - seqsize(2,0)
},
/* saving PRI and then loading from its address
* occurs when indexing a multi-dimensional array
*/
{
"push.pri!load.i!pop.alt!",
"move.alt!load.i!",
seqsize(3,0) - seqsize(2,0)
},
/* An even simpler PUSH/POP optimization (occurs in
* switch statements):
* push.pri move.alt
* pop.alt -
*/
{
"push.pri!pop.alt!",
"move.alt!",
seqsize(2,0) - seqsize(1,0)
},
/* Some simple arithmetic sequences
*/
{
"move.alt!load.s.pri %1!add!",
"load.s.alt %1!add!",
seqsize(3,1) - seqsize(2,1)
},
{
"move.alt!load.pri %1!add!",
"load.alt %1!add!",
seqsize(3,1) - seqsize(2,1)
},
{
"move.alt!const.pri %1!add!",
"const.alt %1!add!",
seqsize(3,1) - seqsize(2,1)
},
{
"move.alt!load.s.pri %1!sub.alt!",
"load.s.alt %1!sub!",
seqsize(3,1) - seqsize(2,1)
},
{
"move.alt!load.pri %1!sub.alt!",
"load.alt %1!sub!",
seqsize(3,1) - seqsize(2,1)
},
{
"move.alt!const.pri %1!sub.alt!",
"const.alt %1!sub!",
seqsize(3,1) - seqsize(2,1)
},
/* User-defined operators first load the operands into registers and
* then have them pushed onto the stack. This can give rise to sequences
* like:
* const.pri n1 push.c n1
* const.alt n2 push.c n2
* push.pri -
* push.alt -
* A similar sequence occurs with the two PUSH.pri/alt instructions inverted.
* The first, second, or both CONST.pri/alt instructions can also be
* LOAD.pri/alt.
* This gives 2 x 4 cases.
*/
{
"const.pri %1!const.alt %2!push.pri!push.alt!",
"push.c %1!push.c %2!",
seqsize(4,2) - seqsize(2,2)
},
{
"const.pri %1!const.alt %2!push.alt!push.pri!",
"push.c %2!push.c %1!",
seqsize(4,2) - seqsize(2,2)
},
{
"const.pri %1!load.alt %2!push.pri!push.alt!",
"push.c %1!push %2!",
seqsize(4,2) - seqsize(2,2)
},
{
"const.pri %1!load.alt %2!push.alt!push.pri!",
"push %2!push.c %1!",
seqsize(4,2) - seqsize(2,2)
},
{
"load.pri %1!const.alt %2!push.pri!push.alt!",
"push %1!push.c %2!",
seqsize(4,2) - seqsize(2,2)
},
{
"load.pri %1!const.alt %2!push.alt!push.pri!",
"push.c %2!push %1!",
seqsize(4,2) - seqsize(2,2)
},
{
"load.pri %1!load.alt %2!push.pri!push.alt!",
"push %1!push %2!",
seqsize(4,2) - seqsize(2,2)
},
{
"load.pri %1!load.alt %2!push.alt!push.pri!",
"push %2!push %1!",
seqsize(4,2) - seqsize(2,2)
},
/* Function calls (parameters are passed on the stack)
* load.s.pri n1 push.s n1
* push.pri -
* --------------------------------------
* load.pri n1 push n1
* push.pri -
* --------------------------------------
* const.pri n1 push.c n1
* push.pri -
* --------------------------------------
* zero.pri push.c 0
* push.pri -
* --------------------------------------
* addr.pri n1 push.adr n1
* push.pri -
*
* However, PRI must not be needed after this instruction
* if this shortcut is used. Check for the ;$par comment.
*/
{
"load.s.pri %1!push.pri!;$par!",
"push.s %1!;$par!",
seqsize(2,1) - seqsize(1,1)
},
{
"load.pri %1!push.pri!;$par!",
"push %1!;$par!",
seqsize(2,1) - seqsize(1,1)
},
{
"const.pri %1!push.pri!;$par!",
"push.c %1!;$par!",
seqsize(2,1) - seqsize(1,1)
},
{
"zero.pri!push.pri!;$par!",
"push.c 0!;$par!",
seqsize(2,0) - seqsize(1,1)
},
{
"addr.pri %1!push.pri!;$par!",
"push.adr %1!;$par!",
seqsize(2,1) - seqsize(1,1)
},
/* References with a default value generate new cells on the heap
* dynamically. That code often ends with:
* move.pri push.alt
* push.pri -
*/
{
"move.pri!push.pri!",
"push.alt!",
seqsize(2,0) - seqsize(1,0)
},
/* Simple arithmetic operations on constants. Noteworthy is the
* subtraction of a constant, since it is converted to the addition
* of the inverse value.
* const.alt n1 add.c n1
* add -
* --------------------------------------
* const.alt n1 add.c -n1
* sub -
* --------------------------------------
* const.alt n1 smul.c n1
* smul -
* --------------------------------------
* const.alt n1 eq.c.pri n1
* eq -
*/
{
"const.alt %1!add!",
"add.c %1!",
seqsize(2,1) - seqsize(1,1)
},
{
"const.alt %1!smul!",
"smul.c %1!",
seqsize(2,1) - seqsize(1,1)
},
{
"const.alt %1!eq!",
"eq.c.pri %1!",
seqsize(2,1) - seqsize(1,1)
},
/* Subtraction of a constant. Note that the subtraction is converted to
* the addition of the inverse value.
* const.pri n1 load.s.pri n2
* load.s.alt n2 add.c -n1
* sub -
* --------------------------------------
* const.pri n1 load.pri n2
* load.alt n2 add.c -n1
* sub -
*/
{
"const.pri %1!load.s.alt %2!sub!",
"load.s.pri %2!add.c -%1!",
seqsize(3,2) - seqsize(2,2)
},
{
"const.pri %1!load.alt %2!sub.alt!",
"load.pri %2!add.c -%1!",
seqsize(3,2) - seqsize(2,2)
},
/* With arrays indexed with constants that come from enumerations, it happens
* multiple add.c opcodes follow in sequence.
* add.c n1 add.c n1+n2
* add.c n2 -
*/
{
"add.c %1!add.c %2!",
"add.c %1+%2!",
seqsize(2,2) - seqsize(1,1)
},
/* Compare and jump
* eq jneq n1
* jzer n1 -
* --------------------------------------
* eq jeq n1
* jnz n1 -
* --------------------------------------
* neq jeq n1
* jzer n1 -
* --------------------------------------
* neq jneq n1
* jnz n1 -
* An similarly for other relations
* sless jsgeq n1
* jzer n1 -
* --------------------------------------
* sless jsless n1
* jnz n1 -
* --------------------------------------
* sleq jsgrtr n1
* jzer n1 -
* --------------------------------------
* sleq jsleq n1
* jnz n1 -
* --------------------------------------
* sgrtr jsleq n1
* jzer n1 -
* --------------------------------------
* sgrtr jsgrtr n1
* jnz n1 -
* --------------------------------------
* sgeq jsless n1
* jzer n1 -
* --------------------------------------
* sgeq jsgeq n1
* jnz n1 -
* We can relax the optimizations for the unsigned comparisons,
* because the Pawn compiler currently only generates signed
* comparisons.
*/
{
"eq!jzer %1!",
"jneq %1!",
seqsize(2,1) - seqsize(1,1)
},
{
"eq!jnz %1!",
"jeq %1!",
seqsize(2,1) - seqsize(1,1)
},
{
"neq!jzer %1!",
"jeq %1!",
seqsize(2,1) - seqsize(1,1)
},
{
"neq!jnz %1!",
"jneq %1!",
seqsize(2,1) - seqsize(1,1)
},
{
"sless!jzer %1!",
"jsgeq %1!",
seqsize(2,1) - seqsize(1,1)
},
{
"sless!jnz %1!",
"jsless %1!",
seqsize(2,1) - seqsize(1,1)
},
{
"sleq!jzer %1!",
"jsgrtr %1!",
seqsize(2,1) - seqsize(1,1)
},
{
"sleq!jnz %1!",
"jsleq %1!",
seqsize(2,1) - seqsize(1,1)
},
{
"sgrtr!jzer %1!",
"jsleq %1!",
seqsize(2,1) - seqsize(1,1)
},
{
"sgrtr!jnz %1!",
"jsgrtr %1!",
seqsize(2,1) - seqsize(1,1)
},
{
"sgeq!jzer %1!",
"jsless %1!",
seqsize(2,1) - seqsize(1,1)
},
{
"sgeq!jnz %1!",
"jsgeq %1!",
seqsize(2,1) - seqsize(1,1)
},
/* Test for zero (common case, especially for strings)
* E.g. the test expression of: "for (i=0; str{i}!=0; ++i)"
*
* zero.alt jzer n1
* jeq n1 -
* --------------------------------------
* zero.alt jnz n1
* jneq n1 -
*/
{
"zero.alt!jeq %1!",
"jzer %1!",
seqsize(2,1) - seqsize(1,1)
},
{
"zero.alt!jneq %1!",
"jnz %1!",
seqsize(2,1) - seqsize(1,1)
},
/* Incrementing and decrementing leaves a value in
* in PRI which may not be used (for example, as the
* third expression in a "for" loop).
* inc n1 inc n1 ; ++n
* load.pri n1 ;$exp
* ;$exp -
* --------------------------------------
* load.pri n1 inc n1 ; n++, e.g. "for (n=0; n<10; n++)"
* inc n1 ;$exp
* ;$exp -
* Plus the varieties for stack relative increments
* and decrements.
*/
{
"inc %1!load.pri %1!;$exp!",
"inc %1!;$exp!",
seqsize(2,2) - seqsize(1,1)
},
{
"load.pri %1!inc %1!;$exp!",
"inc %1!;$exp!",
seqsize(2,2) - seqsize(1,1)
},
{
"inc.s %1!load.s.pri %1!;$exp!",
"inc.s %1!;$exp!",
seqsize(2,2) - seqsize(1,1)
},
{
"load.s.pri %1!inc.s %1!;$exp!",
"inc.s %1!;$exp!",
seqsize(2,2) - seqsize(1,1)
},
{
"dec %1!load.pri %1!;$exp!",
"dec %1!;$exp!",
seqsize(2,2) - seqsize(1,1)
},
{
"load.pri %1!dec %1!;$exp!",
"dec %1!;$exp!",
seqsize(2,2) - seqsize(1,1)
},
{
"dec.s %1!load.s.pri %1!;$exp!",
"dec.s %1!;$exp!",
seqsize(2,2) - seqsize(1,1)
},
{
"load.s.pri %1!dec.s %1!;$exp!",
"dec.s %1!;$exp!",
seqsize(2,2) - seqsize(1,1)
},
/* ??? the same (increments and decrements) for references */
/* Loading the constant zero has a special opcode.
* When storing zero in memory, the value of PRI must not be later on.
* const.pri 0 zero n1
* stor.pri n1 ;$exp
* ;$exp -
* --------------------------------------
* const.pri 0 zero.s n1
* stor.s.pri n1 ;$exp
* ;$exp -
* --------------------------------------
* zero.pri zero n1
* stor.pri n1 ;$exp
* ;$exp -
* --------------------------------------
* zero.pri zero.s n1
* stor.s.pri n1 ;$exp
* ;$exp -
* --------------------------------------
* const.pri 0 zero.pri
* --------------------------------------
* const.alt 0 zero.alt
* The last two alternatives save more memory than they save
* time, but anyway...
*/
{
"const.pri 0!stor.pri %1!;$exp!",
"zero %1!;$exp!",
seqsize(2,2) - seqsize(1,1)
},
{
"const.pri 0!stor.s.pri %1!;$exp!",
"zero.s %1!;$exp!",
seqsize(2,2) - seqsize(1,1)
},
{
"zero.pri!stor.pri %1!;$exp!",
"zero %1!;$exp!",
seqsize(2,1) - seqsize(1,1)
},
{
"zero.pri!stor.s.pri %1!;$exp!",
"zero.s %1!;$exp!",
seqsize(2,1) - seqsize(1,1)
},
{
"const.pri 0!",
"zero.pri!",
seqsize(1,1) - seqsize(1,0)
},
{
"const.alt 0!",
"zero.alt!",
seqsize(1,1) - seqsize(1,0)
},
/* ------------------ */
/* Macro instructions */
/* ------------------ */
{ "", "", 0 }, /* separator, so optimizer can stop before generating macro opcodes */
/* optimizing the calling of native functions (which always have a parameter
* count pushed before, and the stack pointer restored afterwards
*/
{
"push.c %1!sysreq.c %2!stack %3!", /* note: %3 == %1 + 4 */
"sysreq.n %2 %1!",
seqsize(3,3) - seqsize(1,2)
},
/* ----- */
/* Functions with many parameters with the same "type" have sequences like:
* push.c n1 push3.c n1 n2 n3
* ;$par ;$par
* push.c n2 -
* ;$par -
* push.c n3 -
* ;$par -
* etc. etc.
*
* Similar sequences occur with PUSH, PUSH.s and PUSHADDR
*/
{
"push.c %1!;$par!push.c %2!;$par!push.c %3!;$par!push.c %4!;$par!push.c %5!;$par!",
"push5.c %1 %2 %3 %4 %5!",
seqsize(5,5) - seqsize(1,5)
},
{
"push.c %1!;$par!push.c %2!;$par!push.c %3!;$par!push.c %4!;$par!",
"push4.c %1 %2 %3 %4!",
seqsize(4,4) - seqsize(1,4)
},
{
"push.c %1!;$par!push.c %2!;$par!push.c %3!;$par!",
"push3.c %1 %2 %3!",
seqsize(3,3) - seqsize(1,3)
},
{
"push.c %1!;$par!push.c %2!;$par!",
"push2.c %1 %2!",
seqsize(2,2) - seqsize(1,2)
},
/* ----- */
{
"push %1!;$par!push %2!;$par!push %3!;$par!push %4!;$par!push %5!;$par!",
"push5 %1 %2 %3 %4 %5!",
seqsize(5,5) - seqsize(1,5)
},
{
"push %1!;$par!push %2!;$par!push %3!;$par!push %4!;$par!",
"push4 %1 %2 %3 %4!",
seqsize(4,4) - seqsize(1,4)
},
{
"push %1!;$par!push %2!;$par!push %3!;$par!",
"push3 %1 %2 %3!",
seqsize(3,3) - seqsize(1,3)
},
{
"push %1!;$par!push %2!;$par!",
"push2 %1 %2!",
seqsize(2,2) - seqsize(1,2)
},
/* ----- */
{
"push.s %1!;$par!push.s %2!;$par!push.s %3!;$par!push.s %4!;$par!push.s %5!;$par!",
"push5.s %1 %2 %3 %4 %5!",
seqsize(5,5) - seqsize(1,5)
},
{
"push.s %1!;$par!push.s %2!;$par!push.s %3!;$par!push.s %4!;$par!",
"push4.s %1 %2 %3 %4!",
seqsize(4,4) - seqsize(1,4)
},
{
"push.s %1!;$par!push.s %2!;$par!push.s %3!;$par!",
"push3.s %1 %2 %3!",
seqsize(3,3) - seqsize(1,3)
},
{
"push.s %1!;$par!push.s %2!;$par!",
"push2.s %1 %2!",
seqsize(2,2) - seqsize(1,2)
},
/* ----- */
{
"push.adr %1!;$par!push.adr %2!;$par!push.adr %3!;$par!push.adr %4!;$par!push.adr %5!;$par!",
"push5.adr %1 %2 %3 %4 %5!",
seqsize(5,5) - seqsize(1,5)
},
{
"push.adr %1!;$par!push.adr %2!;$par!push.adr %3!;$par!push.adr %4!;$par!",
"push4.adr %1 %2 %3 %4!",
seqsize(4,4) - seqsize(1,4)
},
{
"push.adr %1!;$par!push.adr %2!;$par!push.adr %3!;$par!",
"push3.adr %1 %2 %3!",
seqsize(3,3) - seqsize(1,3)
},
{
"push.adr %1!;$par!push.adr %2!;$par!",
"push2.adr %1 %2!",
seqsize(2,2) - seqsize(1,2)
},
/* Loading two registers at a time
* load.pri n1 load.both n1 n2
* load.alt n2 -
* --------------------------------------
* load.alt n2 load.both n1 n2
* load.pri n1 -
* --------------------------------------
* load.s.pri n1 load.s.both n1 n2
* load.s.alt n2 -
* --------------------------------------
* load.s.alt n2 load.s.both n1 n2
* load.s.pri n1 -
*/
{
"load.pri %1!load.alt %2!",
"load.both %1 %2!",
seqsize(2,2) - seqsize(1,2)
},
{
"load.alt %2!load.pri %1!",
"load.both %1 %2!",
seqsize(2,2) - seqsize(1,2)
},
{
"load.s.pri %1!load.s.alt %2!",
"load.s.both %1 %2!",
seqsize(2,2) - seqsize(1,2)
},
{
"load.s.alt %2!load.s.pri %1!",
"load.s.both %1 %2!",
seqsize(2,2) - seqsize(1,2)
},
/* Loading two registers and then pushing them occurs with user operators
* load.both n1 n2 push2 n1 n2
* push.pri -
* push.alt -
* --------------------------------------
* load.s.both n1 n2 push2.s n1 n2
* push.pri -
* push.alt -
*/
{
"load.both %1 %2!push.pri!push.alt!",
"push2 %1 %2!",
seqsize(3,2) - seqsize(1,2)
},
{
"load.s.both %1 %2!push.pri!push.alt!",
"push2.s %1 %2!",
seqsize(3,2) - seqsize(1,2)
},
/* Load a constant in a variable
* const.pri n1 const n2 n1
* stor.pri n2 -
* --------------------------------------
* const.pri n1 const.s n2 n1
* stor.s.pri n2 -
*/
{
"const.pri %1!stor.pri %2!",
"const %2 %1!",
seqsize(2,2) - seqsize(1,2)
},
{
"const.pri %1!stor.s.pri %2!",
"const.s %2 %1!",
seqsize(2,2) - seqsize(1,2)
},
/* ----- */
{ NULL, NULL, 0 }
};
static int stgstring(char *start,char *end);
static void stgopt(char *start,char *end,int (*outputfunc)(char *str));
#define sSTG_GROW 512
#define sSTG_MAX 20480
static char *stgbuf=NULL;
static int stgmax=0; /* current size of the staging buffer */
static int stglen=0; /* current length of the staging buffer */
static char *stgpipe=NULL;
static int pipemax=0; /* current size of the stage pipe, a second staging buffer */
static int pipeidx=0;
#define CHECK_STGBUFFER(index) if ((int)(index)>=stgmax) grow_stgbuffer(&stgbuf, &stgmax, (index)+1)
#define CHECK_STGPIPE(index) if ((int)(index)>=pipemax) grow_stgbuffer(&stgpipe, &pipemax, (index)+1)
static void grow_stgbuffer(char **buffer, int *curmax, int requiredsize)
{
char *p;
int clear= (*buffer==NULL); /* if previously none, empty buffer explicitly */
assert(*curmax<requiredsize);
/* if the staging buffer (holding intermediate code for one line) grows
* over a few kBytes, there is probably a run-away expression
*/
if (requiredsize>sSTG_MAX)
error(102,"staging buffer"); /* staging buffer overflow (fatal error) */
*curmax=requiredsize+sSTG_GROW;
if (*buffer!=NULL)
p=(char *)realloc(*buffer,*curmax*sizeof(char));
else
p=(char *)malloc(*curmax*sizeof(char));
if (p==NULL)
error(102,"staging buffer"); /* staging buffer overflow (fatal error) */
*buffer=p;
if (clear)
**buffer='\0';
}
SC_FUNC void stgbuffer_cleanup(void)
{
if (stgbuf!=NULL) {
free(stgbuf);
stgbuf=NULL;
stglen=0;
stgmax=0;
} /* if */
if (stgpipe!=NULL) {
free(stgpipe);
stgpipe=NULL;
pipemax=0;
pipeidx=0;
} /* if */
}
/* the variables "stgidx" and "staging" are declared in "scvars.c" */
/* stgmark
*
* Copies a mark into the staging buffer. At this moment there are three
* possible marks:
* sSTARTREORDER identifies the beginning of a series of expression
* strings that must be written to the output file in
* reordered order
* sENDREORDER identifies the end of 'reverse evaluation'
* sEXPRSTART + idx only valid within a block that is evaluated in
* reordered order, it identifies the start of an
* expression; the "idx" value is the argument position
*
* Global references: stgidx (altered)
* stgbuf (altered)
* staging (referred to only)
*/
SC_FUNC void stgmark(char mark)
{
if (staging) {
CHECK_STGBUFFER(stgidx);
stgbuf[stgidx++]=mark;
stglen++;
} /* if */
}
static int rebuffer(char *str)
{
if (sc_status==statWRITE) {
int st_len=strlen(str);
if (pipeidx>=2 && stgpipe[pipeidx-1]=='\0' && stgpipe[pipeidx-2]!='\n')
pipeidx-=1; /* overwrite last '\0' */
CHECK_STGPIPE(pipeidx+st_len+1);
memcpy(stgpipe+pipeidx,str,st_len+1); /* copy to staging buffer */
pipeidx+=st_len+1;
} /* if */
return TRUE;
}
static int filewrite(char *str)
{
if (sc_status==statWRITE)
return pc_writeasm(outf,str);
return TRUE;
}
/* stgwrite
*
* Writes the string "st" to the staging buffer or to the output file. In the
* case of writing to the staging buffer, the terminating byte of zero is
* copied too, but... the optimizer can only work on complete lines (not on
* fractions of it. Therefore if the string is staged, if the last character
* written to the buffer is a '\0' and the previous-to-last is not a '\n',
* the string is concatenated to the last string in the buffer (the '\0' is
* overwritten). This also means an '\n' used in the middle of a string isn't
* recognized and could give wrong results with the optimizer.
* Even when writing to the output file directly, all strings are buffered
* until a whole line is complete.
*
* Global references: stgidx (altered)
* stgbuf (altered)
* staging (referred to only)
* stglen (altered)
*/
SC_FUNC void stgwrite(const char *st)
{
int len;
int st_len=strlen(st);
if (staging) {
assert(stgidx==0 || stgbuf!=NULL); /* staging buffer must be valid if there is (apparently) something in it */
if (stgidx>=2 && stgbuf[stgidx-1]=='\0' && stgbuf[stgidx-2]!='\n')
stgidx-=1; /* overwrite last '\0' */
CHECK_STGBUFFER(stgidx+st_len+1);
memcpy(stgbuf+stgidx,st,st_len+1); /* copy to staging buffer */
stgidx+=st_len+1;
stglen+=st_len;
} else {
len=(stgbuf!=NULL) ? stglen : 0;
CHECK_STGBUFFER(len+st_len+1);
memcpy(stgbuf+len,st,st_len+1);
len=len+st_len;
stglen=len;
if (len>0 && stgbuf[len-1]=='\n') {
filewrite(stgbuf);
stgbuf[0]='\0';
stglen=0;
} /* if */
} /* if */
}
/* stgout
*
* Writes the staging buffer to the output file via stgstring() (for
* reversing expressions in the buffer) and stgopt() (for optimizing). It
* resets "stgidx".
*
* Global references: stgidx (altered)
* stgbuf (referred to only)
* staging (referred to only)
*/
SC_FUNC void stgout(int index)
{
int reordered=0;
int idx;
if (!staging)
return;
assert(pipeidx==0);
/* first pass: sub-expressions */
if (sc_status==statWRITE)
reordered=stgstring(&stgbuf[index],&stgbuf[stgidx]);
stglen=stgidx-index;
stgidx=index;
/* second pass: optimize the buffer created in the first pass */
if (sc_status==statWRITE) {
if (reordered) {
stgopt(stgpipe,stgpipe+pipeidx,filewrite);
} else {
/* there is no sense in re-optimizing if the order of the sub-expressions
* did not change; so output directly
*/
for (idx=0; idx<pipeidx; idx+=strlen(stgpipe+idx)+1)
filewrite(stgpipe+idx);
} /* if */
} /* if */
if (stgidx<=emit_stgbuf_idx)
emit_stgbuf_idx=-1;
pipeidx=0; /* reset second pipe */
}
typedef struct {
char *start,*end;
} argstack;
/* stgstring
*
* Analyses whether code strings should be output to the file as they appear
* in the staging buffer or whether portions of it should be re-ordered.
* Re-ordering takes place in function argument lists; Pawn passes arguments
* to functions from right to left. When arguments are "named" rather than
* positional, the order in the source stream is indeterminate.
* This function calls itself recursively in case it needs to re-order code
* strings, and it uses a private stack (or list) to mark the start and the
* end of expressions in their correct (reversed) order.
* In any case, stgstring() sends a block as large as possible to the
* optimizer stgopt().
*
* In "reorder" mode, each set of code strings must start with the token
* sEXPRSTART, even the first. If the token sSTARTREORDER is represented
* by '[', sENDREORDER by ']' and sEXPRSTART by '|' the following applies:
* '[]...' valid, but useless; no output
* '[|...] valid, but useless; only one string
* '[|...|...] valid and usefull
* '[...|...] invalid, first string doesn't start with '|'
* '[|...|] invalid
*/
static int stgstring(char *start,char *end)
{
char *ptr;
int nest,argc,arg;
argstack *stack;
int reordered=0;
while (start<end) {
if (*start==sSTARTREORDER) {
start+=1; /* skip token */
/* allocate a argstack with sMAXARGS items */
stack=(argstack *)malloc(sMAXARGS*sizeof(argstack));
if (stack==NULL)
error(103); /* insufficient memory */
reordered=1; /* mark that the expression is reordered */
nest=1; /* nesting counter */
argc=0; /* argument counter */
arg=-1; /* argument index; no valid argument yet */
do {
switch (*start) {
case sSTARTREORDER:
nest++;
start++;
break;
case sENDREORDER:
nest--;
start++;
break;
default:
if ((*start & sEXPRSTART)==sEXPRSTART) {
if (nest==1) {
if (arg>=0)
stack[arg].end=start-1; /* finish previous argument */
arg=(unsigned char)*start - sEXPRSTART;
stack[arg].start=start+1;
if (arg>=argc)
argc=arg+1;
} /* if */
start++;
} else {
start+=strlen(start)+1;
} /* if */
} /* switch */
} while (nest); /* enddo */
if (arg>=0)
stack[arg].end=start-1; /* finish previous argument */
while (argc>0) {
argc--;
stgstring(stack[argc].start,stack[argc].end);
} /* while */
free(stack);
} else {
ptr=start;
while (ptr<end && *ptr!=sSTARTREORDER)
ptr+=strlen(ptr)+1;
stgopt(start,ptr,rebuffer);
start=ptr;
} /* if */
} /* while */
return reordered;
}
/* stgdel
*
* Scraps code from the staging buffer by resetting "stgidx" to "index".
*
* Global references: stgidx (altered)
* staging (reffered to only)
*/
SC_FUNC void stgdel(int index,cell code_index)
{
if (staging) {
stgidx=index;
code_idx=code_index;
} /* if */
}
SC_FUNC int stgget(int *index,cell *code_index)
{
if (staging) {
*index=stgidx;
*code_index=code_idx;
} /* if */
return staging;
}
/* stgset
*
* Sets staging on or off. If it's turned off, the staging buffer must be
* initialized to an empty string. If it's turned on, the routine makes sure
* the index ("stgidx") is set to 0 (it should already be 0).
*
* Global references: staging (altered)
* stgidx (altered)
* stgbuf (contents altered)
*/
SC_FUNC void stgset(int onoff)
{
staging=onoff;
if (staging){
assert(stgidx==0);
stgidx=0;
CHECK_STGBUFFER(stgidx);
/* write any contents that may be put in the buffer by stgwrite()
* when "staging" was 0
*/
if (stglen>0)
filewrite(stgbuf);
} /* if */
stgbuf[0]='\0';
stglen=0;
}
#define MAX_OPT_VARS 5
#define MAX_OPT_CAT 5 /* max. values that are concatenated */
#if sNAMEMAX > (PAWN_CELL_SIZE/4) * MAX_OPT_CAT
#define MAX_ALIAS sNAMEMAX
#else
#define MAX_ALIAS (PAWN_CELL_SIZE/4) * MAX_OPT_CAT
#endif
static int matchsequence(char *start,char *end,char *pattern,
char symbols[MAX_OPT_VARS][MAX_ALIAS+1],
int *match_length)
{
int var,i;
char str[MAX_ALIAS+1];
char *start_org=start;
cell value;
char *ptr;
*match_length=0;
for (var=0; var<MAX_OPT_VARS; var++)
symbols[var][0]='\0';
while (*start=='\t' || *start==' ')
start++;
while (*pattern) {
if (start>=end)
return FALSE;
switch (*pattern) {
case '%': /* new "symbol" */
pattern++;
assert(isdigit(*pattern));
var=atoi(pattern) - 1;
assert(var>=0 && var<MAX_OPT_VARS);
assert(*start=='-' || alphanum(*start));
for (i=0; start<end && (*start=='-' || *start=='+' || alphanum(*start)); i++,start++) {
assert(i<=MAX_ALIAS);
str[i]=*start;
} /* for */
str[i]='\0';
if (symbols[var][0]!='\0') {
if (strcmp(symbols[var],str)!=0)
return FALSE; /* symbols should be identical */
} else {
strcpy(symbols[var],str);
} /* if */
break;
case '-':
value=-strtol(pattern+1,&pattern,16);
ptr=itoh((ucell)value);
while (*ptr!='\0') {
if (tolower(*start) != tolower(*ptr))
return FALSE;
start++;
ptr++;
} /* while */
pattern--; /* there is an increment following at the end of the loop */
break;
case ' ':
if (*start!='\t' && *start!=' ')
return FALSE;
while (start<end && (*start=='\t' || *start==' '))
start++;
break;
case '!':
while (start<end && (*start=='\t' || *start==' '))
start++; /* skip trailing white space */
if (*start==';')
while (start<end && *start!='\n')
start++; /* skip trailing comment */
if (*start!='\n')
return FALSE;
assert(*(start+1)=='\0');
start+=2; /* skip '\n' and '\0' */
if (*(pattern+1)!='\0')
while ((start<end && *start=='\t') || *start==' ')
start++; /* skip leading white space of next instruction */
break;
default:
if (tolower(*start) != tolower(*pattern))
return FALSE;
start++;
} /* switch */
pattern++;
} /* while */
*match_length=(int)(start-start_org);
return TRUE;
}
static char *replacesequence(char *pattern,char symbols[MAX_OPT_VARS][MAX_ALIAS+1],int *repl_length)
{
char *lptr;
int var;
char *buffer;
/* calculate the length of the new buffer
* this is the length of the pattern plus the length of all symbols (note
* that the same symbol may occur multiple times in the pattern) plus
* line endings and startings ('\t' to start a line and '\n\0' to end one)
*/
assert(repl_length!=NULL);
*repl_length=0;
lptr=pattern;
while (*lptr) {
switch (*lptr) {
case '%':
lptr++; /* skip '%' */
assert(isdigit(*lptr));
var=atoi(lptr) - 1;
assert(var>=0 && var<MAX_OPT_VARS);
assert(symbols[var][0]!='\0'); /* variable should be defined */
*repl_length+=strlen(symbols[var]);
break;
case '!':
*repl_length+=3; /* '\t', '\n' & '\0' */
break;
default:
*repl_length+=1;
} /* switch */
lptr++;
} /* while */
/* allocate a buffer to replace the sequence in */
if ((buffer=(char*)malloc(*repl_length))==NULL) {
error(103);
return NULL;
} /* if */
/* replace the pattern into this temporary buffer */
lptr=buffer;
*lptr++='\t'; /* the "replace" patterns do not have tabs */
while (*pattern) {
assert((int)(lptr-buffer)<*repl_length);
switch (*pattern) {
case '%':
/* write out the symbol */
pattern++;
assert(isdigit(*pattern));
var=atoi(pattern) - 1;
assert(var>=0 && var<MAX_OPT_VARS);
assert(symbols[var][0]!='\0'); /* variable should be defined */
strcpy(lptr,symbols[var]);
lptr+=strlen(symbols[var]);
break;
case '!':
/* finish the line, optionally start the next line with an indent */
*lptr++='\n';
*lptr++='\0';
if (*(pattern+1)!='\0')
*lptr++='\t';
break;
default:
*lptr++=*pattern;
} /* switch */
pattern++;
} /* while */
assert((int)(lptr-buffer)==*repl_length);
return buffer;
}
static void strreplace(char *dest,char *replace,int sub_length,int repl_length,int dest_length)
{
int offset=sub_length-repl_length;
if (offset>0) { /* delete a section */
memmove(dest,dest+offset,dest_length-offset);
memset(dest+dest_length-offset,0xcc,offset); /* not needed, but for cleanlyness */
} else if (offset<0) { /* insert a section */
memmove(dest-offset, dest, dest_length);
} /* if */
memcpy(dest, replace, repl_length);
}
/* stgopt
*
* Optimizes the staging buffer by checking for series of instructions that
* can be coded more compact. The routine expects the lines in the staging
* buffer to be separated with '\n' and '\0' characters.
*
* The longest sequences should probably be checked first.
*/
static void stgopt(char *start,char *end,int (*outputfunc)(char *str))
{
char symbols[MAX_OPT_VARS][MAX_ALIAS+1];
int seq,match_length,repl_length;
int matches;
char *debut=start; /* save original start of the buffer */
assert(sequences!=NULL);
/* do not match anything if debug-level is maximum */
if (pc_optimize>sOPTIMIZE_NONE && sc_status==statWRITE && emit_stgbuf_idx==-1) {
do {
matches=0;
start=debut;
while (start<end) {
seq=0;
while (sequences[seq].find!=NULL) {
assert(seq>=0);
if (*sequences[seq].find=='\0') {
if (pc_optimize==sOPTIMIZE_NOMACRO) {
break; /* don't look further */
} else {
seq++; /* continue with next string */
continue;
} /* if */
} /* if */
if (matchsequence(start,end,sequences[seq].find,symbols,&match_length)) {
char *replace=replacesequence(sequences[seq].replace,symbols,&repl_length);
/* If the replacement is bigger than the original section, we may need
* to "grow" the staging buffer. This is quite complex, due to the
* re-ordering of expressions that can also happen in the staging
* buffer. In addition, it should not happen: the peephole optimizer
* must replace sequences with *shorter* sequences, not longer ones.
* So, I simply forbid sequences that are longer than the ones they
* are meant to replace.
*/
assert(match_length>=repl_length);
if (match_length>=repl_length) {
strreplace(start,replace,match_length,repl_length,(int)(end-start));
end-=match_length-repl_length;
free(replace);
code_idx-=sequences[seq].savesize;
seq=0; /* restart search for matches */
matches++;
} else {
/* actually, we should never get here (match_length<repl_length) */
assert(0);
seq++;
} /* if */
} else {
seq++;
} /* if */
} /* while */
assert(sequences[seq].find==NULL || *sequences[seq].find=='\0' && pc_optimize==sOPTIMIZE_NOMACRO);
start += strlen(start) + 1; /* to next string */
} /* while (start<end) */
} while (matches>0);
} /* if (pc_optimize>sOPTIMIZE_NONE && sc_status==statWRITE) */
for (start=debut; start<end; start+=strlen(start)+1)
outputfunc(start);
}