https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113421
Bug ID: 113421
Summary: wrong code with -O -fno-tree-fre and _BitInt()
multiplication
Product: gcc
Version: 14.0
Status: UNCONFIRMED
Keywords: wrong-code
Severity: normal
Priority: P3
Component: tree-optimization
Assignee: unassigned at gcc dot gnu.org
Reporter: zsojka at seznam dot cz
Target Milestone: ---
Host: x86_64-pc-linux-gnu
Target: x86_64-pc-linux-gnu
Created attachment 57101
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=57101&action=edit
reduced testcase
Output:
$ x86_64-pc-linux-gnu-gcc testcase.c -O -fno-tree-fre
$ ./a.out
Aborted
On the asm level:
...
mov r9d, 1024 #,
lea r8, [rsp+16] #,
mov ecx, 1024 #,
mov edx, OFFSET FLAT:g #,
mov esi, 1024 #,
mov rdi, rdx #,
call __mulbitint3 #
...
rdi == rdx, overlapping the "ret" and "u" arguments of __mulbitint3
$ x86_64-pc-linux-gnu-gcc -v
Using built-in specs.
COLLECT_GCC=/repo/gcc-trunk/binary-latest-amd64/bin/x86_64-pc-linux-gnu-gcc
COLLECT_LTO_WRAPPER=/repo/gcc-trunk/binary-trunk-r14-7274-20240116114934-g1251d3957de-checking-yes-rtl-df-extra-nobootstrap-amd64/bin/../libexec/gcc/x86_64-pc-linux-gnu/14.0.1/lto-wrapper
Target: x86_64-pc-linux-gnu
Configured with: /repo/gcc-trunk//configure --enable-languages=c,c++
--enable-valgrind-annotations --disable-nls --enable-checking=yes,rtl,df,extra
--disable-bootstrap --with-cloog --with-ppl --with-isl
--build=x86_64-pc-linux-gnu --host=x86_64-pc-linux-gnu
--target=x86_64-pc-linux-gnu --with-ld=/usr/bin/x86_64-pc-linux-gnu-ld
--with-as=/usr/bin/x86_64-pc-linux-gnu-as --disable-libstdcxx-pch
--prefix=/repo/gcc-trunk//binary-trunk-r14-7274-20240116114934-g1251d3957de-checking-yes-rtl-df-extra-nobootstrap-amd64
Thread model: posix
Supported LTO compression algorithms: zlib zstd
gcc version 14.0.1 20240116 (experimental) (GCC)
