| Message ID | 201203261157.q2QBvPPF015131@d06av02.portsmouth.uk.ibm.com |
|---|---|
| State | New |
| Headers | show |
On Mon, Mar 26, 2012 at 1:57 PM, Ulrich Weigand <uweigand@de.ibm.com> wrote: > Hello, > > one of Ira's vectorizer patches I recently committed seems to have exposed > a pre-existing bug in handling WIDEN_LSHIFT_EXPR, which now causes ICEs > in SLP due to out-of-bounds memory accesses. > > The underlying cause is that vect_get_smallest_scalar_type does not handle > WIDEN_LSHIFT_EXPR as it does the other widening operations. This causes > the SLP pass to operate on the wrong type and thus get confused about the > number of vector instructions it need to allocate space for. > > The following patch fixes all those ICEs for me. Manual checking shows > that widening shifts are now recognized correctly by SLP. > > Tested with no regression on armv7l-linux-gnueabi and i686-linux-gnu. > > OK for mainline? Ok. Thanks, Richard. > Bye, > Ulrich > > > ChangeLog: > > gcc/ > PR tree-optimization/52686 > * tree-vect-data-refs.c (vect_get_smallest_scalar_type): Handle > WIDEN_LSHIFT_EXPR. > > gcc/testsuite/ > PR tree-optimization/52686 > * gcc.target/arm/pr52686.c: New test. > > > Index: gcc/testsuite/gcc.target/arm/pr52686.c > =================================================================== > --- gcc/testsuite/gcc.target/arm/pr52686.c (revision 0) > +++ gcc/testsuite/gcc.target/arm/pr52686.c (revision 0) > @@ -0,0 +1,19 @@ > +/* PR target/52375 */ > +/* { dg-do compile } */ > +/* { dg-require-effective-target arm_neon_ok } */ > +/* { dg-options "-march=armv7-a -mfloat-abi=softfp -mfpu=neon -O -ftree-vectorize" } */ > + > +unsigned int output[4]; > + > +void test (unsigned short *p) > +{ > + unsigned int x = *p; > + if (x) > + { > + output[0] = x << 1; > + output[1] = x << 1; > + output[2] = x << 1; > + output[3] = x << 1; > + } > +} > + > Index: gcc/tree-vect-data-refs.c > =================================================================== > --- gcc/tree-vect-data-refs.c (revision 185467) > +++ gcc/tree-vect-data-refs.c (working copy) > @@ -111,6 +111,7 @@ > if (is_gimple_assign (stmt) > && (gimple_assign_cast_p (stmt) > || gimple_assign_rhs_code (stmt) == WIDEN_MULT_EXPR > + || gimple_assign_rhs_code (stmt) == WIDEN_LSHIFT_EXPR > || gimple_assign_rhs_code (stmt) == FLOAT_EXPR)) > { > tree rhs_type = TREE_TYPE (gimple_assign_rhs1 (stmt)); > -- > Dr. Ulrich Weigand > GNU Toolchain for Linux on System z and Cell BE > Ulrich.Weigand@de.ibm.com >
Index: gcc/testsuite/gcc.target/arm/pr52686.c =================================================================== --- gcc/testsuite/gcc.target/arm/pr52686.c (revision 0) +++ gcc/testsuite/gcc.target/arm/pr52686.c (revision 0) @@ -0,0 +1,19 @@ +/* PR target/52375 */ +/* { dg-do compile } */ +/* { dg-require-effective-target arm_neon_ok } */ +/* { dg-options "-march=armv7-a -mfloat-abi=softfp -mfpu=neon -O -ftree-vectorize" } */ + +unsigned int output[4]; + +void test (unsigned short *p) +{ + unsigned int x = *p; + if (x) + { + output[0] = x << 1; + output[1] = x << 1; + output[2] = x << 1; + output[3] = x << 1; + } +} + Index: gcc/tree-vect-data-refs.c =================================================================== --- gcc/tree-vect-data-refs.c (revision 185467) +++ gcc/tree-vect-data-refs.c (working copy) @@ -111,6 +111,7 @@ if (is_gimple_assign (stmt) && (gimple_assign_cast_p (stmt) || gimple_assign_rhs_code (stmt) == WIDEN_MULT_EXPR + || gimple_assign_rhs_code (stmt) == WIDEN_LSHIFT_EXPR || gimple_assign_rhs_code (stmt) == FLOAT_EXPR)) { tree rhs_type = TREE_TYPE (gimple_assign_rhs1 (stmt));