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Sometimes pc-relative addressing needs no relocation record.

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In this case, in an absolute section refering to an absolute symbol.
Use test cases from Johnny Billquist.
This commit is contained in:
Olaf Seibert 2020-03-07 15:41:20 +01:00
parent 62868a6661
commit c4221e0b4b
7 changed files with 205 additions and 5 deletions
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2
README
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@ -32,7 +32,7 @@ USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
DAMAGE.
modified 2009 by Joerg Hoppe,
modified 2015-2017 by Olaf 'Rhialto' Seibert.
modified 2015-2017,2020 by Olaf 'Rhialto' Seibert.
Files:
macro11.c Command line parsing and driving the passes.

12
assemble_aux.c
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@ -467,12 +467,18 @@ void mode_extension(
}
if (value->type == EX_LIT) {
if (mode->rel) /* PC-relative? */
store_displaced_word(str, tr, 2, value->data.lit);
else
if (mode->rel) { /* PC-relative? */
if (current_pc->section->flags & PSECT_REL) {
store_displaced_word(str, tr, 2, value->data.lit);
} else {
/* I can compute this myself. */
store_word(str, tr, 2, value->data.lit - DOT - 2);
}
} else {
store_word(str, tr, 2, value->data.lit); /* Just a
known
value. */
}
} else if (express_sym_offset(value, &sym, &offset)) {
if ((sym->flags & (SYMBOLFLAG_GLOBAL | SYMBOLFLAG_DEFINITION)) == SYMBOLFLAG_GLOBAL) {
/* Reference to a global symbol. */

2
macro11.c
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@ -80,7 +80,7 @@ static void print_version(
fprintf(strm, " Version %s\n", VERSIONSTR);
fprintf(strm, " Copyright 2001 Richard Krehbiel,\n");
fprintf(strm, " modified 2009 by Joerg Hoppe,\n");
fprintf(strm, " modified 2015-2017 by Olaf 'Rhialto' Seibert.\n");
fprintf(strm, " modified 2015-2017,2020 by Olaf 'Rhialto' Seibert.\n");
}
static void append_env(

1
tests/RunTests
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@ -23,6 +23,7 @@ TESTS="test-asciz \
test-prec \
test-psect \
test-rad50 \
test-reloc \
test-rept \
test-ua-pl \
test-undef \

89
tests/test-reloc.lst.ok Normal file
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@ -0,0 +1,89 @@
1 .TITLE Test references that need (no) relocation
2
3 000000 .PSECT FOO,I,RW
4
5 000000 000042 .WORD 42
6 000002 000000 Y: .WORD 0
7
8 ; absolute expression since the offset to the pc is a
9 ; subtraction of the relative address of Y from the current
10 ; position, both in the same psect. Such an operation renders
11 ; an absolute value.
12 000004 005067 177772 CLR Y
13
14 ; relocatable, since the absolute address of Y is unknown because
15 ; it's in a psect that can be moved around at link time.
16 000010 005037 000002' CLR @#Y
17
18 ; relocatable because even though X is at a known address, the
19 ; address of the instruction is unknown and subject to the location
20 ; of the psect, which is only decided at link time.
21 000014 005067 001234' CLR X
22
23 ; absolute since it is an expression only dependent on an
24 ; absolute value.
25 000020 005037 001234 CLR @#X
26
27 ; Test AMA (uses absolute addresses rather than pc-relative)
28
29 .enabl AMA
30
31 ; Could be relative, as above, but AMA forces it to @#Y and
32 ; then it needs relocation again, weirdly enough.
33 000024 005037 000002' clr Y
34 ; Same as @#X.
35 000030 005037 001234 clr X
36
37 .dsabl AMA
38
39 000000 .ASECT
40 001000 .=1000
41
42 001234 X=1234
43 ; relocatable because the address of Y is in another psect, and
44 ; the subtraction of a relative address from an absolute renders
45 ; a relative value.
46 001000 005067 000002' CLR Y
47
48 ; relocatable because the absolute address of Y is unknown.
49 ; MACRO-11 only have a relative value of Y.
50 001004 005037 000002' CLR @#Y
51
52 ; absolute since the offset to the pc is an expression subtracting
53 ; two absolute values which obviously have an absolute result.
54 001010 005067 000220 CLR X
55
56 ; absolute since it is an expression only dependent on an
57 ; absolute value.
58 001014 005037 001234 CLR @#X
59
60 ; Note that all references to Y contains 000002. This is because
61 ; that is the offset of Y within the psect. This is added to the
62 ; base of the psect (the part that comes from this object file),
63 ; which is all the linker will know about.
64
65 ; Test AMA
66
67 .enabl AMA
68
69 ; Same as @#Y.
70 001020 005037 000002' clr Y
71 ; Same as @#X.
72 001024 005037 001234 clr X
73
74 .dsabl AMA
75
76 .END
76
Symbol table
. =****** X =001234 Y 000002R 002
Program sections:
. ABS. 001030 000 (RW,I,GBL,ABS,OVR,NOSAV)
000000 001 (RW,I,LCL,REL,CON,NOSAV)
FOO 000034 002 (RW,I,LCL,REL,CON,NOSAV)

76
tests/test-reloc.mac Normal file
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@ -0,0 +1,76 @@
.TITLE Test references that need (no) relocation
.PSECT FOO,I,RW
.WORD 42
Y: .WORD 0
; absolute expression since the offset to the pc is a
; subtraction of the relative address of Y from the current
; position, both in the same psect. Such an operation renders
; an absolute value.
CLR Y
; relocatable, since the absolute address of Y is unknown because
; it's in a psect that can be moved around at link time.
CLR @#Y
; relocatable because even though X is at a known address, the
; address of the instruction is unknown and subject to the location
; of the psect, which is only decided at link time.
CLR X
; absolute since it is an expression only dependent on an
; absolute value.
CLR @#X
; Test AMA (uses absolute addresses rather than pc-relative)
.enabl AMA
; Could be relative, as above, but AMA forces it to @#Y and
; then it needs relocation again, weirdly enough.
clr Y
; Same as @#X.
clr X
.dsabl AMA
.ASECT
.=1000
X=1234
; relocatable because the address of Y is in another psect, and
; the subtraction of a relative address from an absolute renders
; a relative value.
CLR Y
; relocatable because the absolute address of Y is unknown.
; MACRO-11 only have a relative value of Y.
CLR @#Y
; absolute since the offset to the pc is an expression subtracting
; two absolute values which obviously have an absolute result.
CLR X
; absolute since it is an expression only dependent on an
; absolute value.
CLR @#X
; Note that all references to Y contains 000002. This is because
; that is the offset of Y within the psect. This is added to the
; base of the psect (the part that comes from this object file),
; which is all the linker will know about.
; Test AMA
.enabl AMA
; Same as @#Y.
clr Y
; Same as @#X.
clr X
.dsabl AMA
.END

28
tests/test-reloc.objd.ok Normal file
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@ -0,0 +1,28 @@
GSD:
MODNAME TEST =0 flags=0
PSECT =0 CON RW REL LCL I flags=40
PSECT . ABS.=1030 OVR RW ABS GBL I flags=104
PSECT FOO =34 CON RW REL LCL I flags=40
XFER . ABS.=1 flags=10
ENDGSD
RLD
Location counter definition FOO+0
TEXT ADDR=0 LEN=34
000000: 000042 000000 005067 177772 "...7...
000010: 005037 000002 005067 001234 ....7...
000020: 005037 001234 005037 000002 ........
000030: 005037 001234 ....
RLD
Internal 12=2
Internal displaced 16=1234
Internal 26=2
Location counter definition . ABS.+1000
TEXT ADDR=1000 LEN=30
001000: 005067 000002 005037 000002 7.......
001010: 005067 000220 005037 001234 7.......
001020: 005037 000002 005037 001234 ........
RLD
PSECT plus offset displaced 1002=FOO+2
PSECT plus offset 1006=FOO+2
PSECT plus offset 1022=FOO+2
ENDMOD