[Bug target/77300] [MIPS] incorrectly moves instruction containing local GOT16 relocation into a delay slot

[james410 at cowgill dot org.uk]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77300

--- Comment #3 from James Cowgill <james410 at cowgill dot org.uk> ---
$ mipsel-linux-gnu-readelf -r src.o

Relocation section '.rel.text' at offset 0x584 contains 6 entries:
 Offset     Info    Type            Sym.Value  Sym. Name
00000000  00001005 R_MIPS_HI16       00000000   _gp_disp
00000004  00001006 R_MIPS_LO16       00000000   _gp_disp
00000010  0000170b R_MIPS_CALL16     00000000   _ZN1GC1Ei
00000028  00001725 R_MIPS_JALR       00000000   _ZN1GC1Ei
00000038  0000130b R_MIPS_CALL16     00000000   _ZN1HIiE5m_fn5ERK1G
0000003c  00001325 R_MIPS_JALR       00000000   _ZN1HIiE5m_fn5ERK1G

Relocation section '.rel.pdr' at offset 0x5b4 contains 3 entries:
 Offset     Info    Type            Sym.Value  Sym. Name
00000000  00000702 R_MIPS_32         00000000   _ZN1HIiE5m_fn4ERK1G.is
00000020  00001302 R_MIPS_32         00000000   _ZN1HIiE5m_fn5ERK1G
00000040  00001802 R_MIPS_32         00000000   _Z3fn1v

Relocation section '.rel.text._ZN1HIiE5m_fn4ERK1G.isra.1' at offset 0x5cc
contains 6 entries:
 Offset     Info    Type            Sym.Value  Sym. Name
00000000  00001005 R_MIPS_HI16       00000000   _gp_disp
00000004  00001006 R_MIPS_LO16       00000000   _gp_disp
00000010  0000110b R_MIPS_CALL16     00000000   _ZN1DC1EP1C
00000030  00001125 R_MIPS_JALR       00000000   _ZN1DC1EP1C
00000044  0000120b R_MIPS_CALL16     00000000   _ZN1HIiE5m_fn3EP1C
00000048  00001225 R_MIPS_JALR       00000000   _ZN1HIiE5m_fn3EP1C

Relocation section '.rel.text._ZN1HIiE5m_fn5ERK1G' at offset 0x5fc contains 18
entries:
 Offset     Info    Type            Sym.Value  Sym. Name
00000000  00001005 R_MIPS_HI16       00000000   _gp_disp
00000004  00001006 R_MIPS_LO16       00000000   _gp_disp
00000010  0000140b R_MIPS_CALL16     00000000   _ZN1HIiE5m_fn2Ev
00000028  00001425 R_MIPS_JALR       00000000   _ZN1HIiE5m_fn2Ev
00000038  0000150b R_MIPS_CALL16     00000000   _ZN1HIiE5m_fn1Ev
0000003c  00001525 R_MIPS_JALR       00000000   _ZN1HIiE5m_fn1Ev
00000048  0000160b R_MIPS_CALL16     00000000   _ZN1HIiE5m_fn6Ev
0000004c  00001625 R_MIPS_JALR       00000000   _ZN1HIiE5m_fn6Ev
0000005c  00000709 R_MIPS_GOT16      00000000   _ZN1HIiE5m_fn4ERK1G.is
00000060  00000706 R_MIPS_LO16       00000000   _ZN1HIiE5m_fn4ERK1G.is
00000068  00000725 R_MIPS_JALR       00000000   _ZN1HIiE5m_fn4ERK1G.is
00000074  00000725 R_MIPS_JALR       00000000   _ZN1HIiE5m_fn4ERK1G.is
00000094  0000170b R_MIPS_CALL16     00000000   _ZN1GC1Ei
0000009c  00001725 R_MIPS_JALR       00000000   _ZN1GC1Ei
000000b0  0000150b R_MIPS_CALL16     00000000   _ZN1HIiE5m_fn1Ev
000000b4  00001525 R_MIPS_JALR       00000000   _ZN1HIiE5m_fn1Ev
000000cc  00000709 R_MIPS_GOT16      00000000   _ZN1HIiE5m_fn4ERK1G.is
000000d4  0000150b R_MIPS_CALL16     00000000   _ZN1HIiE5m_fn1Ev

Relocation section '.rel.eh_frame' at offset 0x68c contains 3 entries:
 Offset     Info    Type            Sym.Value  Sym. Name
0000001c  00000602 R_MIPS_32         00000000   .text._ZN1HIiE5m_fn4ER
00000054  00000802 R_MIPS_32         00000000   .text._ZN1HIiE5m_fn5ER
00000090  00000202 R_MIPS_32         00000000   .text

$ mipsel-linux-gnu-gcc -fuse-ld=bfd src.o
[... omitted irrelevant undefined references]
/usr/lib/gcc-cross/mipsel-linux-gnu/6/../../../../mipsel-linux-gnu/bin/ld.bfd:
src.o: Can't find matching LO16 reloc against `_ZN1HIiE5m_fn4ERK1G.isra.1' for
R_MIPS_GOT16 at 0xcc in section
`.text._ZN1HIiE5m_fn5ERK1G[_ZN1HIiE5m_fn5ERK1G]'
[...]

$ mipsel-linux-gnu-gcc -fuse-ld=gold src.o 
/usr/lib/gcc-cross/mipsel-linux-gnu/6/../../../../mipsel-linux-gnu/bin/ld.gold:
error: Can't find matching LO16 reloc
/usr/lib/gcc-cross/mipsel-linux-gnu/6/../../../../mipsel-linux-gnu/bin/ld.gold:
error: Can't find matching LO16 reloc
/usr/lib/gcc-cross/mipsel-linux-gnu/6/../../../../mipsel-linux-gnu/bin/ld.gold:
error: Can't find matching LO16 reloc
/usr/lib/gcc-cross/mipsel-linux-gnu/6/../../../../mipsel-linux-gnu/bin/ld.gold:
error: Can't find matching LO16 reloc
[...]