While working on disassembler styling for MIPS, I noticed that
undefined instructions are printed by the disassembler as raw number
with no assembler directive prefix (e.g. without .word or .short).
I think adding something like .word, or .short, helps to make it
clearer the size of the value that is being displayed, and is inline
with what many of the other libopcode disassemblers do.
In this commit I've added the .word and .short directives, and updated
all the tests that I spotted that failed as a result.
Correct issues with INSN2_ALIAS annotation for branch instructions:
- regular MIPS BEQZ/L and BNEZ/L assembly instructions are idioms for
BEQ/L and BNE/L respectively with the `rs' operand equal to $0,
- microMIPS 32-bit BEQZ and BNEZ assembly instructions are idioms for
BEQ and BNE respectively with the `rt' operand equal to $0,
- regular MIPS BAL assembly instruction is an idiom for architecture
levels of up to the MIPSr5 ISA and a machine instruction on its own
from the MIPSr6 ISA up.
Add missing annotation to BEQZ/L and BNEZ/L accordingly then and add a
new entry for BAL for the MIPSr6 ISA, correcting a disassembly bug:
$ mips-linux-gnu-objdump -m mips:isa64r6 -M no-aliases -d bal.o
bal.o: file format elf32-tradlittlemips
Disassembly of section .text:
00000000 <foo>:
0: 04110000 0x4110000
...
$
Add test cases accordingly.
Parts for regular MIPS BEQZ/L and BNEZ/L instructions from Sagar Patel.
2022-03-06 Maciej W. Rozycki <macro@orcam.me.uk>
binutils/
* testsuite/binutils-all/mips/mips1-branch-alias.d: New test.
* testsuite/binutils-all/mips/mips1-branch-noalias.d: New test.
* testsuite/binutils-all/mips/mips2-branch-alias.d: New test.
* testsuite/binutils-all/mips/mips2-branch-noalias.d: New test.
* testsuite/binutils-all/mips/mips32r6-branch-alias.d: New test.
* testsuite/binutils-all/mips/mips32r6-branch-noalias.d: New
test.
* testsuite/binutils-all/mips/micromips-branch-alias.d: New
test.
* testsuite/binutils-all/mips/micromips-branch-noalias.d: New
test.
* testsuite/binutils-all/mips/mips-branch-alias.s: New test
source.
* testsuite/binutils-all/mips/micromips-branch-alias.s: New test
source.
* testsuite/binutils-all/mips/mips.exp: Run the new tests.
2022-03-06 Sagar Patel <sagarmp@cs.unc.edu>
Maciej W. Rozycki <macro@orcam.me.uk>
opcodes/
* mips-opc.c (mips_builtin_opcodes): Fix INSN2_ALIAS annotation
for "bal", "beqz", "beqzl", "bnez" and "bnezl" instructions.
* micromips-opc.c (micromips_opcodes): Likewise for "beqz" and
"bnez" instructions.
