From 287f8d5d70bdbc90e9bd0013209e35dc085a8c61 Mon Sep 17 00:00:00 2001 From: ceriel Date: Wed, 1 Nov 1989 17:30:44 +0000 Subject: [PATCH] fixed Constant Width --- doc/ceg/ceg.tr | 88 +++++++++++++++++++++++++++++--------------------- 1 file changed, 52 insertions(+), 36 deletions(-) diff --git a/doc/ceg/ceg.tr b/doc/ceg/ceg.tr index bf66d58ef..140c1b16f 100644 --- a/doc/ceg/ceg.tr +++ b/doc/ceg/ceg.tr @@ -158,13 +158,15 @@ One of the most fundamental operations in EM is ``loc c'', load the value of c on the stack. To expand this instruction the tables contain the following information: .DS -EM_table : \fCW +EM_table : +.ft CW C_loc ==> "pushl $$$1". /* $1 refers to the first argument of C_loc. * $$ is a quoted $. */ -\fRas_table :\fCW +\fRas_table : +.ft CW pushl src : CONST ==> @text1( 0xd0); @text1( 0xef); @@ -174,7 +176,7 @@ EM_table : \fCW .LP The as_table is transformed in the following routine: .DS -\fCW +.ft CW pushl_instr(src) t_operand *src; /* ``t_operand'' is a struct defined by the @@ -189,7 +191,7 @@ t_operand *src; .DE Using ``pushl_instr()'', the following routine is generated from the EM_table: .DS -\fCW +.ft CW C_loc( c) arith c; /* text1() and text4() are library routines that fill the @@ -335,7 +337,7 @@ the speed of the actual code expander. Finally, actions can be grouped into a list of actions; actions are separated by a semicolon and terminated by a ``.''. .DS -\fCW +.ft CW C_nop ==> . /* Empty action list : no operation. */ @@ -362,7 +364,7 @@ action list. .LP The following example illustrates the usage of labels. .DS -\fCW +.ft CW /* Compare the two top elements on the stack. */ C_cmp ==> "pop bx"; "pop cx"; @@ -397,7 +399,7 @@ The value of the $\fIi\fR argument referring to a parameter ($\fIi\fR >= 0) is increased by ``EM_BSIZE''. ``EM_BSIZE'' is the size of the return status block and must be defined in the file ``mach.h'' (see section 3.3). For example : .DS -\fCW +.ft CW C_lol ==> "push $1(bp)". /* automatic conversion of $1 */ \fR @@ -409,7 +411,7 @@ transformed into a unique assembly name. To prevent name clashes with library names the table writer has to provide the conversions in the file ``mach.h''. For example : .DS -\fCW +.ft CW C_bra ==> "jmp $1". /* automatic conversion of $1 */ /* type arith is converted to string */ @@ -435,7 +437,7 @@ The boolean expressions in a COND_SEQUENCE must be C expressions. Besides the ordinary C operators and constants, $\fIi\fR references can be used in an expression. .DS -\fCW +.ft CW /* Load address of LB $1 levels back. */ C_lxl $1 == 0 ==> "pushl fp". @@ -454,7 +456,7 @@ these variants together. For this purpose the ``..'' notation is introduced. For the code expander there is no difference between the following instructions. .DS -\fCW +.ft CW C_loe_dlb ==> "pushl $1 + $2". C_loe_dnam ==> "pushl $1 + $2". C_loe ==> "pushl $1 + $2". @@ -462,7 +464,7 @@ C_loe ==> "pushl $1 + $2". .DE So it can be written in the following way. .DS -\fCW +.ft CW C_loe.. ==> "pushl $1 + $2". \fR .DE @@ -481,7 +483,7 @@ Most pseudo instructions are machine independent and are provided by \fBceg\fR. The table writer has only to supply the following functions, which are used to build a stackframe: .DS -\fCW +.ft CW C_prolog() /* Performs the prolog, for example save * return address */ @@ -512,7 +514,7 @@ C_rom_icon, C_con_icon, C_bss_icon, C_hol_icon can be abbreviated by ..icon. This also holds for ..ucon and ..fcon. For example : .DS -\fCW +.ft CW \\.\\.icon $2 == 1 ==> gen1( (ONE_BYTE) atoi( $1)). $2 == 2 ==> gen2( (TWO_BYTES) atoi( $1)). @@ -630,7 +632,7 @@ There are three primitives that have to be defined by the table writer, either as functions in the file ``mach.c'' or as rules in the EM_table. For example, for the 8086 they look like this: .DS -\fCW +.ft CW C_jump ==> "jmp $1". C_prolog ==> "push bp"; @@ -781,7 +783,7 @@ right hand side gives the corresponding actions as \fBback\fR-primitives or as functions defined by the table writer, which call \fBback-primitives\fR. Two simple examples from the VAX as_table and the 8086 as_table, resp.: .DS -\fCW +.ft CW movl src, dst ==> @text1( 0xd0); gen_operand( src); gen_operand( dst). @@ -822,7 +824,7 @@ that each mnemonic is mentioned only once in the as_table, otherwise .PP The following example shows the usage of type fields. .DS -\fCW +.ft CW mov dst:REG, src:EADDR ==> @text1( 0x8b); /* opcode */ mod_RM( %d(dst->reg), src). /* operands */ @@ -832,8 +834,11 @@ The following example shows the usage of type fields. mod_RM( %d(src->reg), dst). /* operands */ \fR .DE -The table-writer must supply the restriction functions, \fCWREG\fR and -\fCWEADDR\fR in the previous example, in ``as.c'' or ''as.h''. +The table-writer must supply the restriction functions, +.ft CW +REG\fR and +.ft CW +EADDR\fR in the previous example, in ``as.c'' or ''as.h''. .NH 3 The function of the @-sign and the if-statement. .PP @@ -842,7 +847,9 @@ Since the as_table is interpreted on two levels, during code expander generation and during code expander execution, two levels of calls are present in it. A function-call without an ``@''-sign -is called during code expander generation (e.g., the \fCWgen_operand()\fR in the +is called during code expander generation (e.g., the +.ft CW +gen_operand()\fR in the first example). A function call with an ``@''-sign is called during code expander execution (e.g., @@ -854,7 +861,7 @@ can be replaced by ``move x, y''). In this case flags need to be set, unset, and tested during the execution of the compiler: .DS L -\fCW +.ft CW PUSH src ==> /* save in ax */ mov_instr( AX_oper, src); /* set flag */ @@ -862,7 +869,7 @@ PUSH src ==> /* save in ax */ \fR .DE .DS -\fCW +.ft CW POP dst ==> @if ( push_waiting) /* ``mov_instr'' is asg-generated */ mov_instr( dst, AX_oper); @@ -889,7 +896,7 @@ run time of the \fBce\fR. In such a condition one may of course refer to the ''$\fIi\fR'' arguments. For example, constants can be packed into one or two byte arguments as follows: .DS -\fCW +.ft CW mov dst:ACCU, src:DATA ==> @if ( fits_byte( %$(dst->expr))) @text1( 0xc0); @@ -948,7 +955,7 @@ The following example illustrates the usage of ``%$''. (For an example that illustrates the usage of ordinary fields see the section on ``User supplied definitions and functions''). .DS -\fCW +.ft CW jmp dst ==> @text1( 0xe9); @reloc2( %$(dst->lab), %$(dst->off), PC_REL). @@ -969,7 +976,7 @@ and reloc4() calls, saving space and time (no relocation at compiler run time). The following example illustrates the usage of ``%dist''. .DS -\fCW +.ft CW jmp dst:ILB ==> /* label in an instruction list */ @text1( 0xeb); @text1( %dist( dst->lab)). @@ -1012,7 +1019,7 @@ below). If the default assemble() does not work the way the table writer wants, he can supply his own version of it. Assemble() has the following arguments: .DS -\fCW +.ft CW assemble( instruction ) char *instruction; \fR @@ -1027,7 +1034,7 @@ required on a block of assembly instructions, the table writer only has to rewrite this function to get a new \fBceg\fR that obliges to his wishes. The function block_assemble has the following arguments: .DS -\fCW +.ft CW block_assemble( instructions, nr, first, last) char **instruction; int nr, first, last; @@ -1053,7 +1060,7 @@ The following example shows the representative and essential parts of the .nr VS 12 .LP .DS L -\fCW +.ft CW /* Constants and type definitions in as.h */ #define UNKNOWN 0 @@ -1101,7 +1108,7 @@ extern struct t_operand saved_op, *AX_oper; .nr PS 10 .nr VS 12 .DS L -\fCW +.ft CW /* Some functions in as.c. */ @@ -1261,7 +1268,7 @@ for ``as_table'', ``as.h'', and ``as.c'' at this moment. .IP \0\03: type .br -\fCW +.ft CW install_ceg -as \fR .br @@ -1272,7 +1279,9 @@ one for each EM-instruction. All these files will be compiled and put in a library called \fBce.a\fR. .br -The option \fCW-as\fR means that a \fBback\fR-library will be +The option +.ft CW +-as\fR means that a \fBback\fR-library will be generated (in the directory ``back'') that supports the generation of assembly language. The library is named ``back.a''. .IP \0\04: @@ -1284,7 +1293,7 @@ tested (e.g., by running the compiler on the EM test set). If an error occurs, change the EM_table and type .IP .br -\fCW +.ft CW update_ceg\fR \fBC_instr \fR .br @@ -1305,13 +1314,18 @@ Write the ``as_table'', ``as.h'', and ``as.c'' files. .IP \0\03: type .sp -\fCW install_ceg -obj \fR +.ft CW +install_ceg -obj \fR .sp -The option \fCW-obj\fR means that ``back.a'' will contain a library +The option +.ft CW +-obj\fR means that ``back.a'' will contain a library for generating ACK.OUT(5ACK) object files, see appendix B. If the writer does not want to use the default ``back.a'', -the \fCW-obj\fR flag must omitted and a ``back.a'' should be supplied that +the +.ft CW +-obj\fR flag must omitted and a ``back.a'' should be supplied that generates the generates object code in the desired format. .IP \0\04: Link a front end, ``ce.a'', and ``back.a'' together resulting in a compiler @@ -1322,12 +1336,14 @@ Then there are two ways to proceed: .IP \0\01: recompile the whole EM_table, .sp -\fCW update_ceg ALL \fR +.ft CW +update_ceg ALL \fR .sp .IP \0\02: recompile just the few EM-instructions that contained the error, .sp -\fCW update_ceg \fBC_instr\fR +.ft CW +update_ceg \fBC_instr\fR .sp where \fBC_instr\fR is an erroneous EM-instruction. This has to be done for every EM-instruction that contained the erroneous -- 2.34.1