[Bug rtl-optimization/70284] New: ICE: in replace_rtx at rtlanal.c for mips n32

["faraz.shahbazker at imgtec dot com" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70284

            Bug ID: 70284
           Summary: ICE: in replace_rtx at rtlanal.c for mips n32
           Product: gcc
           Version: 6.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: rtl-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: faraz.shahbazker at imgtec dot com
  Target Milestone: ---

Created attachment 38005
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=38005&action=edit
Minimal test case

New assert in commit 867c9e995539beefa594475f2bd831438e36a077 causes ICE for
mips64 n32. Minimal test-case attached, failure found while building glibc.

$ ./install-mips-mti-linux-gnu/bin/mips-mti-linux-gnu-gcc -v -save-temps
-mips64 -mabi=n32 -O2 -c test.c
Using built-in specs.
COLLECT_GCC=./install-mips-mti-linux-gnu/bin/mips-mti-linux-gnu-gcc
Target: mips-mti-linux-gnu
Configured with: /scratch/frs/src/gcc/configure
--prefix=/scratch/frs/install-mips-mti-linux-gnu --disable-libssp
--disable-libmudflap --disable-decimal-float --with-mips-plt
--target=mips-mti-linux-gnu --enable-languages=c --without-headers
--disable-shared --disable-threads --disable-libquadmath --disable-libatomic
--with-sysroot=/scratch/frs/install-mips-mti-linux-gnu/sysroot --enable-debug
Thread model: single
gcc version 6.0.0 20160317 (experimental) (GCC) 
COLLECT_GCC_OPTIONS='-v' '-save-temps' '-mips64' '-mabi=n32' '-O2' '-c'
'-mllsc' '-mplt' '-mno-synci' '-mno-shared' '-EB'

/scratch/frs/install-mips-mti-linux-gnu/libexec/gcc/mips-mti-linux-gnu/6.0.0/cc1
-E -quiet -v -isysroot
/scratch/frs/install-mips-mti-linux-gnu/sysroot/mips-r1-hard test.c -meb
-mips64 -mabi=n32 -mllsc -mplt -mno-synci -mno-shared -O2 -fpch-preprocess -o
test.i
ignoring nonexistent directory
"/scratch/frs/install-mips-mti-linux-gnu/sysroot/mips-r1-hard/usr/local/include"
ignoring nonexistent directory
"/scratch/frs/install-mips-mti-linux-gnu/lib/gcc/mips-mti-linux-gnu/6.0.0/../../../../mips-mti-linux-gnu/include"
#include "..." search starts here:
#include <...> search starts here:

/scratch/frs/install-mips-mti-linux-gnu/lib/gcc/mips-mti-linux-gnu/6.0.0/include

/scratch/frs/install-mips-mti-linux-gnu/lib/gcc/mips-mti-linux-gnu/6.0.0/include-fixed
 /scratch/frs/install-mips-mti-linux-gnu/sysroot/mips-r1-hard/usr/include
End of search list.
COLLECT_GCC_OPTIONS='-v' '-save-temps' '-mips64' '-mabi=n32' '-O2' '-c'
'-mllsc' '-mplt' '-mno-synci' '-mno-shared' '-EB'

/scratch/frs/install-mips-mti-linux-gnu/libexec/gcc/mips-mti-linux-gnu/6.0.0/cc1
-fpreprocessed test.i -meb -quiet -dumpbase test.c -mips64 -mabi=n32 -mllsc
-mplt -mno-synci -mno-shared -auxbase test -O2 -version -o test.s
GNU C11 (GCC) version 6.0.0 20160317 (experimental) (mips-mti-linux-gnu)
        compiled by GNU C version 4.4.7 20120313 (Red Hat 4.4.7-16), GMP
version 4.3.2, MPFR version 3.0.1, MPC version 0.9, isl version none
GGC heuristics: --param ggc-min-expand=30 --param ggc-min-heapsize=4096
GNU C11 (GCC) version 6.0.0 20160317 (experimental) (mips-mti-linux-gnu)
        compiled by GNU C version 4.4.7 20120313 (Red Hat 4.4.7-16), GMP
version 4.3.2, MPFR version 3.0.1, MPC version 0.9, isl version none
GGC heuristics: --param ggc-min-expand=30 --param ggc-min-heapsize=4096
Compiler executable checksum: 93ffb79b8f803fb23bc523b8a8a85910
test.c: In function âtestâ:
test.c:6:1: internal compiler error: in replace_rtx, at rtlanal.c:2969
 }
 ^
0xa69cde replace_rtx(rtx_def*, rtx_def*, rtx_def*)
        /scratch/frs/src/gcc/gcc/rtlanal.c:2969
0xa69dba replace_rtx(rtx_def*, rtx_def*, rtx_def*)
        /scratch/frs/src/gcc/gcc/rtlanal.c:3009
0xf9fa57 record_value_for_reg
        /scratch/frs/src/gcc/gcc/combine.c:12673
0xfadca2 combine_instructions
        /scratch/frs/src/gcc/gcc/combine.c:1488
0xfadca2 rest_of_handle_combine
        /scratch/frs/src/gcc/gcc/combine.c:14345
0xfadca2 execute
        /scratch/frs/src/gcc/gcc/combine.c:14388
Please submit a full bug report,
with preprocessed source if appropriate.