[PATCH] PR libfortran/99218 - [8/9/10/11 Regression] matmul on temporary array accesses invalid memory

[Harald Anlauf]

Dear all,

under certain circumstances a call to MATMUL for rank-2 times rank-1
would invoke a highly tuned rank-2 times rank-2 algorithm which could
lead to invalid reads and writes.  The solution is to check the rank
of the second argument to matmul and fall back to a regular algorithm
for rank-1.  The invalid accesses did show up with valgrind.

I have not been able to create a testcase that gives wrong results.

Regtested on x86_64-pc-linux-gnu, and verified with valgrind.

OK for master?

As this affects all open branches down to 8, ok for backports?

Thanks,
Harald


PR libfortran/99218 - matmul on temporary array accesses invalid memory

Do not invoke tuned rank-2 times rank-2 matmul if rank(b) == 1.

libgfortran/ChangeLog:

	PR libfortran/99218
	* m4/matmul_internal.m4: Invoke tuned matmul only for rank(b)>1.
	* generated/matmul_c10.c: Regenerated.
        * generated/matmul_c16.c: Likewise.
        * generated/matmul_c4.c: Likewise.
        * generated/matmul_c8.c: Likewise.
        * generated/matmul_i1.c: Likewise.
        * generated/matmul_i16.c: Likewise.
        * generated/matmul_i2.c: Likewise.
        * generated/matmul_i4.c: Likewise.
        * generated/matmul_i8.c: Likewise.
        * generated/matmul_r10.c: Likewise.
        * generated/matmul_r16.c: Likewise.
        * generated/matmul_r4.c: Likewise.
        * generated/matmul_r8.c: Likewise.
        * generated/matmulavx128_c10.c: Likewise.
        * generated/matmulavx128_c16.c: Likewise.
        * generated/matmulavx128_c4.c: Likewise.
        * generated/matmulavx128_c8.c: Likewise.
        * generated/matmulavx128_i1.c: Likewise.
        * generated/matmulavx128_i16.c: Likewise.
        * generated/matmulavx128_i2.c: Likewise.
        * generated/matmulavx128_i4.c: Likewise.
        * generated/matmulavx128_i8.c: Likewise.
        * generated/matmulavx128_r10.c: Likewise.
        * generated/matmulavx128_r16.c: Likewise.
        * generated/matmulavx128_r4.c: Likewise.
        * generated/matmulavx128_r8.c: Likewise.

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