# HG changeset patch
# User lost@starbug
# Date 1271299744 21600
# Node ID 6a98cc90c14f6be0746f7ded6d12671f7eac0f75
# Parent 0b5a26bedbe16443d0d16828c07cb34986eecb84
Added resolve passes
diff -r 0b5a26bedbe1 -r 6a98cc90c14f doc/internals.txt
--- a/doc/internals.txt Tue Apr 06 21:35:09 2010 -0600
+++ b/doc/internals.txt Wed Apr 14 20:49:04 2010 -0600
@@ -24,38 +24,13 @@
------
This pass resolves all instruction sizes that can be resolved without
-setting addresses for instructions. This process is repeated until no
-further instructions sizes are resolved.
+forcing any instruction sizes. This pass will run repeatedly until no
+no new resolution occurs.
Pass 4
------
-This pass assigns addresses to all symbols where values are known. It does
-the same for instructions. Then a repeat of similar algorithms as in the
-previous pass is used to resolve as many operands as possible.
-
-This pass is repeated multiple times until no further instructions or
-symbols are resolved.
-
-Pass 5
-------
-
-Finalization of all instruction sizes by forcing them to the maximum
-addressing mode. Then all remaining instruction addresses and symbol values
-are resolved.
-
-Pass 6
-------
-
-This pass does actual code generation. This is the notional second pass. All
-other passes are the notional first pass.
-
-
-Expression Evaluation
-=====================
-
-Each expression carries a certainty flag. Any expression in which any term
-is flagged as uncertain is, itself, uncertain. There are a few specific
-cases where such uncertainty can cancel out. For instance, X-X where X is
-uncertain is guaranteed to be 0 and so there is no uncertainty.
-
+Work through all un-resolved instructions and force sizes. After each size
+is forced, try re-resolving all other instructions. This is done starting
+at the beginning of the source and working forward. If any instruction does
+not resolve when forced, an error will be thrown.
diff -r 0b5a26bedbe1 -r 6a98cc90c14f lwasm/Makefile.am
--- a/lwasm/Makefile.am Tue Apr 06 21:35:09 2010 -0600
+++ b/lwasm/Makefile.am Wed Apr 14 20:49:04 2010 -0600
@@ -1,7 +1,7 @@
AM_CPPFLAGS = -I$(top_builddir)/lib -I$(top_srcdir)/lib -I$(top_builddir)/lwlib -I$(top_srcdir)/lwlib
bin_PROGRAMS = lwasm
lwasm_SOURCES = main.c pragma.c input.c pass1.c lwasm.c \
- instab.c symbol.c macro.c pass2.c pass3.c \
+ instab.c symbol.c macro.c pass2.c pass3.c pass4.c \
insn_inh.c insn_rtor.c insn_tfm.c insn_rlist.c insn_rel.c \
insn_bitbit.c insn_indexed.c insn_gen.c insn_logicmem.c \
pseudo.c section.c os9.c
diff -r 0b5a26bedbe1 -r 6a98cc90c14f lwasm/main.c
--- a/lwasm/main.c Tue Apr 06 21:35:09 2010 -0600
+++ b/lwasm/main.c Wed Apr 14 20:49:04 2010 -0600
@@ -167,6 +167,7 @@
extern void do_pass1(asmstate_t *as);
extern void do_pass2(asmstate_t *as);
extern void do_pass3(asmstate_t *as);
+extern void do_pass4(asmstate_t *as);
extern lw_expr_t lwasm_evaluate_special(int t, void *ptr, void *priv);
extern lw_expr_t lwasm_evaluate_var(char *var, void *priv);
extern lw_expr_t lwasm_parse_term(char **p, void *priv);
@@ -179,6 +180,7 @@
{ "parse", do_pass1 },
{ "symcheck", do_pass2 },
{ "resolve1", do_pass3 },
+ { "resolve2", do_pass4 },
{ NULL, NULL }
};
diff -r 0b5a26bedbe1 -r 6a98cc90c14f lwasm/pass3.c
--- a/lwasm/pass3.c Tue Apr 06 21:35:09 2010 -0600
+++ b/lwasm/pass3.c Wed Apr 14 20:49:04 2010 -0600
@@ -39,4 +39,37 @@
*/
void do_pass3(asmstate_t *as)
{
+ int rc;
+ line_t *cl;
+ struct line_expr_s *le;
+
+ do
+ {
+ rc = 0;
+ for (cl = as -> line_head; cl; cl = cl -> next)
+ {
+ as -> cl = cl;
+
+ // simplify address
+ lwasm_reduce_expr(as, cl -> addr);
+
+ // simplify each expression
+ for (le = cl -> exprs; le; le = le -> next)
+ lwasm_reduce_expr(as, le -> expr);
+
+ if (cl -> len == -1)
+ {
+ // try resolving the instruction length
+ // but don't force resolution
+ if (cl -> insn >= 0 && instab[cl -> insn].resolve)
+ {
+ (instab[cl -> insn].resolve)(as, cl, 0);
+ if (cl -> len != -1)
+ rc++;
+ }
+ }
+ }
+ if (as -> errorcount > 0)
+ return;
+ } while (rc > 0);
}
diff -r 0b5a26bedbe1 -r 6a98cc90c14f lwasm/pass4.c
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/lwasm/pass4.c Wed Apr 14 20:49:04 2010 -0600
@@ -0,0 +1,117 @@
+/*
+pass4.c
+
+Copyright © 2010 William Astle
+
+This file is part of LWTOOLS.
+
+LWTOOLS is free software: you can redistribute it and/or modify it under the
+terms of the GNU General Public License as published by the Free Software
+Foundation, either version 3 of the License, or (at your option) any later
+version.
+
+This program is distributed in the hope that it will be useful, but WITHOUT
+ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+more details.
+
+You should have received a copy of the GNU General Public License along with
+this program. If not, see .
+*/
+
+#include
+
+#include
+#include
+
+#include
+#include
+
+#include "lwasm.h"
+#include "instab.h"
+
+/*
+Resolve2 Pass
+
+Force resolution of instruction sizes.
+
+*/
+void do_pass4(asmstate_t *as)
+{
+ int rc;
+ int cnt;
+ line_t *cl, *sl;
+ struct line_expr_s *le;
+
+ // first, count the number of unresolved instructions
+ for (cnt = 0, cl = as -> line_head; cl; cl = cl -> next)
+ {
+ if (cl -> len == -1)
+ cnt++;
+ }
+
+ sl = as -> line_head;
+ while (cnt > 0)
+ {
+ // find an unresolved instruction
+ for ( ; sl && sl -> len != -1; sl = sl -> next)
+ /* do nothing */ ;
+
+ // simplify address
+ as -> cl = sl;
+ lwasm_reduce_expr(as, sl -> addr);
+
+ // simplify each expression
+ for (le = sl -> exprs; le; le = le -> next)
+ lwasm_reduce_expr(as, le -> expr);
+
+
+ if (sl -> insn >= 0 && instab[sl -> insn].resolve)
+ {
+ (instab[cl -> insn].resolve)(as, sl, 1);
+ if (sl -> len == -1)
+ {
+ lwasm_register_error(as, sl, "Instruction failed to resolve.");
+ return;
+ }
+ }
+ cnt--;
+ if (cnt == 0)
+ return;
+
+ do
+ {
+ rc = 0;
+ for (cl = sl; cl; cl = cl -> next)
+ {
+ as -> cl = cl;
+
+ // simplify address
+ lwasm_reduce_expr(as, cl -> addr);
+
+ // simplify each expression
+ for (le = cl -> exprs; le; le = le -> next)
+ lwasm_reduce_expr(as, le -> expr);
+
+ if (cl -> len == -1)
+ {
+ // try resolving the instruction length
+ // but don't force resolution
+ if (cl -> insn >= 0 && instab[cl -> insn].resolve)
+ {
+ (instab[cl -> insn].resolve)(as, cl, 0);
+ if (cl -> len != -1)
+ {
+ rc++;
+ cnt--;
+ if (cnt == 0)
+ return;
+ }
+ }
+ }
+ }
+ if (as -> errorcount > 0)
+ return;
+ } while (rc > 0);
+ }
+}