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Fix PR 105532: match.pd patterns calling tree_nonzero_bits with vector types

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Even though this PR was reported with an ubsan issue, the problem is
tree_nonzero_bits is being called with an expression which is a vector type.
This fixes three patterns I noticed which does that.
And adds a testcase for one of the patterns.

OK? Bootstrapped and tested on x86_64-linux-gnu with no regressions

gcc/ChangeLog:

	PR tree-optimization/105532
	* match.pd (~(X >> Y) -> ~X >> Y): Check if it is an integral
	type before calling tree_nonzero_bits.
	(popcount(X) + popcount(Y)): Likewise.
	(popcount(X&C1)): Likewise.

gcc/testsuite/ChangeLog:

	* gcc.c-torture/compile/vector-shift-1.c: New test.
This commit is contained in:
Andrew Pinski 2022-11-02 15:56:31 +00:00
parent 91e0d22025
commit 193fccaa5c
2 changed files with 22 additions and 11 deletions
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25
gcc/match.pd
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@ -1370,7 +1370,8 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
/* For logical right shifts, this is possible only if @0 doesn't
have MSB set and the logical right shift is changed into
arithmetic shift. */
(if (!wi::neg_p (tree_nonzero_bits (@0)))
(if (INTEGRAL_TYPE_P (type)
&& !wi::neg_p (tree_nonzero_bits (@0)))
(with { tree stype = signed_type_for (TREE_TYPE (@0)); }
(convert (rshift (bit_not! (convert:stype @0)) @1))))))
@ -7623,7 +7624,8 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
/* popcount(X) + popcount(Y) is popcount(X|Y) when X&Y must be zero. */
(simplify
(plus (POPCOUNT:s @0) (POPCOUNT:s @1))
(if (wi::bit_and (tree_nonzero_bits (@0), tree_nonzero_bits (@1)) == 0)
(if (INTEGRAL_TYPE_P (type)
&& wi::bit_and (tree_nonzero_bits (@0), tree_nonzero_bits (@1)) == 0)
(POPCOUNT (bit_ior @0 @1))))
/* popcount(X) == 0 is X == 0, and related (in)equalities. */
@ -7655,15 +7657,16 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
(for pfun (POPCOUNT PARITY)
(simplify
(pfun @0)
(with { wide_int nz = tree_nonzero_bits (@0); }
(switch
(if (nz == 1)
(convert @0))
(if (wi::popcount (nz) == 1)
(with { tree utype = unsigned_type_for (TREE_TYPE (@0)); }
(convert (rshift:utype (convert:utype @0)
{ build_int_cst (integer_type_node,
wi::ctz (nz)); }))))))))
(if (INTEGRAL_TYPE_P (type))
(with { wide_int nz = tree_nonzero_bits (@0); }
(switch
(if (nz == 1)
(convert @0))
(if (wi::popcount (nz) == 1)
(with { tree utype = unsigned_type_for (TREE_TYPE (@0)); }
(convert (rshift:utype (convert:utype @0)
{ build_int_cst (integer_type_node,
wi::ctz (nz)); })))))))))
#if GIMPLE
/* 64- and 32-bits branchless implementations of popcount are detected:

8
gcc/testsuite/gcc.c-torture/compile/vector-shift-1.c Normal file
View file

@ -0,0 +1,8 @@
typedef unsigned char __attribute__((__vector_size__ (1))) U;
U
foo (U u)
{
u = u == u;
return (~(u >> 255));
}