From: <apinski@marvell.com>
To: <gcc-patches@gcc.gnu.org>
Cc: Andrew Pinski <apinski@marvell.com>
Subject: [PATCH 1/2] Fix PR 105532: match.pd patterns calling tree_nonzero_bits with vector types
Date: Wed, 2 Nov 2022 14:46:34 -0700 [thread overview]
Message-ID: <1667425595-2654-2-git-send-email-apinski@marvell.com> (raw)
In-Reply-To: <1667425595-2654-1-git-send-email-apinski@marvell.com>
From: Andrew Pinski <apinski@marvell.com>
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.
---
gcc/match.pd | 25 +++++++++++--------
.../gcc.c-torture/compile/vector-shift-1.c | 8 ++++++
2 files changed, 22 insertions(+), 11 deletions(-)
create mode 100644 gcc/testsuite/gcc.c-torture/compile/vector-shift-1.c
diff --git a/gcc/match.pd b/gcc/match.pd
index 194ba8f5188..5833e05a926 100644
--- a/gcc/match.pd
+++ b/gcc/match.pd
@@ -1371,7 +1371,8 @@ 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))))))
@@ -7518,7 +7519,8 @@ 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. */
@@ -7550,15 +7552,16 @@ 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:
diff --git a/gcc/testsuite/gcc.c-torture/compile/vector-shift-1.c b/gcc/testsuite/gcc.c-torture/compile/vector-shift-1.c
new file mode 100644
index 00000000000..142ea56d5bb
--- /dev/null
+++ b/gcc/testsuite/gcc.c-torture/compile/vector-shift-1.c
@@ -0,0 +1,8 @@
+typedef unsigned char __attribute__((__vector_size__ (1))) U;
+
+U
+foo (U u)
+{
+ u = u == u;
+ return (~(u >> 255));
+}
--
2.17.1
next prev parent reply other threads:[~2022-11-02 21:46 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-11-02 21:46 [PATCH 0/2] tree_nonzero_bits vs vector and complex types apinski
2022-11-02 21:46 ` apinski [this message]
2022-11-05 11:44 ` [PATCH 1/2] Fix PR 105532: match.pd patterns calling tree_nonzero_bits with vector types Richard Biener
2022-12-20 13:45 ` Richard Biener
2022-11-02 21:46 ` [PATCH 2/2] Add assert for type on tree_nonzero_bits apinski
2022-11-05 11:47 ` Richard Biener
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