[PATCH] PR libfortran/97063 - Wrong result for vector (step size is negative) * matrix

[Harald Anlauf]

PR libfortran/97063 - Wrong result for vector (step size is negative) * matrix
Dear all,

when matrix-multiplying rank-1 times rank-2 arrays, a wrong result was
produced when a negative stride was used for the rank-1 array.  In that
case special code for rank-2 times rank-2 was erroneously executed.
We should never have gotten there, so move the check for rank-1 of the
first argument before that case.

The patch looks horrendously large because it consists essentially of
regenerated code (nearly 99%).

Regtests cleanly on x86_64-pc-linux-gnu.

OK for master?  And backport to all open branches where it applies?

Thanks,
Harald


The MATMUL intrinsic provided a wrong result for rank-1 times rank-2 array
when a negative stride was used for addressing the elements of the rank-1
array, because a check on strides was erroneously placed before the check
on the rank.  Interchange order of checks.

libgfortran/ChangeLog:

	* m4/matmul_internal.m4: Move check for rank-1 times rank-2 before
	checks on strides for rank-2 times rank-2.
	* 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.

gcc/testsuite/ChangeLog:

	* gfortran.dg/matmul_20.f90: New test.

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