https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89826
Bug ID: 89826
Summary: [9 Regression] wrong code at -O1
Product: gcc
Version: 9.0
Status: UNCONFIRMED
Keywords: wrong-code
Severity: normal
Priority: P3
Component: rtl-optimization
Assignee: unassigned at gcc dot gnu.org
Reporter: zsojka at seznam dot cz
Target Milestone: ---
Host: x86_64-pc-linux-gnu
Target: armv7a-hardfloat-linux-gnueabi
Created attachment 46023
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=46023&action=edit
reduced testcase
This seems to be a recent regression.
Output:
$ armv7a-hardfloat-linux-gnueabi-gcc -O testcase.c -static
$ ./a.out
qemu: uncaught target signal 6 (Aborted) - core dumped
Aborted
The upper 32 bits seem to be garbage - r1 is used uninitialized.
@@ -29,6 +29,7 @@
ldr ip, [r3, #4]
cmp r0, #0
mov r3, #0
+ mov r1, r3
mvneq r3, r2
mvneq r1, ip
subs r4, r2, r3
should fix the assembly.
$ armv7a-hardfloat-linux-gnueabi-gcc -v
Using built-in specs.
COLLECT_GCC=/repo/gcc-trunk/binary-latest-armv7a-hardfloat/bin/armv7a-hardfloat-linux-gnueabi-gcc
COLLECT_LTO_WRAPPER=/repo/gcc-trunk/binary-trunk-269932-checking-yes-rtl-df-extra-armv7a-hardfloat/bin/../libexec/gcc/armv7a-hardfloat-linux-gnueabi/9.0.1/lto-wrapper
Target: armv7a-hardfloat-linux-gnueabi
Configured with: /repo/gcc-trunk//configure --enable-languages=c,c++
--enable-valgrind-annotations --disable-nls --enable-checking=yes,rtl,df,extra
--with-cloog --with-ppl --with-isl --with-float=hard --with-fpu=vfpv4
--with-arch=armv7-a --with-sysroot=/usr/armv7a-hardfloat-linux-gnueabi
--build=x86_64-pc-linux-gnu --host=x86_64-pc-linux-gnu
--target=armv7a-hardfloat-linux-gnueabi
--with-ld=/usr/bin/armv7a-hardfloat-linux-gnueabi-ld
--with-as=/usr/bin/armv7a-hardfloat-linux-gnueabi-as --disable-libstdcxx-pch
--prefix=/repo/gcc-trunk//binary-trunk-269932-checking-yes-rtl-df-extra-armv7a-hardfloat
Thread model: posix
gcc version 9.0.1 20190326 (experimental) (GCC)
