b417536f23
Make BFD agree with GAS and mark the LSI MiniRISC CW4010 processor core
(for an odd reason referred to as LSI R4010 across our code base) as a
MIPS II processor in BFD as well, fixing a bug that has been there since
forever and addressing linker warnings like:
$ as -m4010 empty.s -o 4010.o
$ ld -r 4010.o -o 4010-r.o
ld: 4010.o: warning: Inconsistent ISA between e_flags and .MIPS.abiflags
$
due to the ISA level being recorded as MIPS III in ELF file header's
`e_flags' vs MIPS II in the MIPS ABI Flags section:
$ readelf -Ah 4010.o
ELF Header:
Magic: 7f 45 4c 46 01 02 01 00 00 00 00 00 00 00 00 00
Class: ELF32
Data: 2's complement, big endian
Version: 1 (current)
OS/ABI: UNIX - System V
ABI Version: 0
Type: REL (Relocatable file)
Machine: MIPS R3000
Version: 0x1
Entry point address: 0x0
Start of program headers: 0 (bytes into file)
Start of section headers: 348 (bytes into file)
Flags: 0x20821000, 4010, o32, mips3
Size of this header: 52 (bytes)
Size of program headers: 0 (bytes)
Number of program headers: 0
Size of section headers: 40 (bytes)
Number of section headers: 11
Section header string table index: 10
Attribute Section: gnu
File Attributes
Tag_GNU_MIPS_ABI_FP: Hard float (double precision)
MIPS ABI Flags Version: 0
ISA: MIPS2
GPR size: 32
CPR1 size: 32
CPR2 size: 0
FP ABI: Hard float (double precision)
ISA Extension: LSI R4010
ASEs:
None
FLAGS 1: 00000000
FLAGS 2: 00000000
$
Available documentation[1][2] clearly indicates the LSI CW4010 processor
is only backwards compatible with the MIPS R4000 processor as far as the
latter's 32-bit instructions are concerned and consequently can only be
considered a MIPS II ISA implementation (with vendor extensions).
This fixes an LD testsuite failure:
FAIL: MIPS incompatible objects: "-march=r4010 -32" "-march=r4650 -32"
triggered for the `mips-sgi-irix5' and `mips-sgi-irix6' targets.
References:
[1] Paul Cobb, Bob Caulk, Joe Cesana, "The MiniRISC CW4010: A
Superscalar MIPS Processor ASIC Core", LSI Logic, July 1995,
presented at Hot Chips VII, Stanford University, Stanford,
California, August 1995
[2] "MiniRISC MR4010 Superscalar Microprocessor Reference Device", LSI
Logic, November 1996, Doc. No. DB09-000028-00, Order No. C15017
bfd/
* cpu-mips.c (arch_info_struct): Mark the 4010 32-bit.
* elfxx-mips.c (mips_set_isa_flags) <bfd_mach_mips4010>: Set
E_MIPS_ARCH_2 rather than E_MIPS_ARCH_3 in `e_flags'.
(mips_mach_extensions): Mark `bfd_mach_mips4010' as extending
`bfd_mach_mips6000' rather than `bfd_mach_mips4000'.
ld/
* testsuite/ld-mips-elf/lsi-4010-isa.d: New test.
* ld/testsuite/ld-mips-elf/mips-elf.exp: Run the new test.
README for LD
This is the GNU linker. It is distributed with other "binary
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=======================
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===========================
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==============
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