Richard Sandiford <richard.sandif...@arm.com> writes: > In this PR the waccess pass was fed: > > D.10779 ={v} {CLOBBER}; > VIEW_CONVERT_EXPR<svuint64_t[2]>(D.10779) = .MASK_LOAD_LANES (addr_5(D), > 64B, _2); > _7 = D.10779.__val[0]; > > However, the tracking of m_clobbers only looked at gassigns, > so it missed that the clobber on the first line was overwritten > by the call on the second line. > > This patch splits the updating of m_clobbers out into its own > function, called after the check_*() routines, and extends it > to handle both gassigns and gcalls. I think that makes sense > as an instance of the "read, operate, write" model, with the > new function being part of "write". > > Previously only the gimple_clobber_p handling was conditional > on m_check_dangling_p, but I think the whole of the new function > can be. We only enter stmts into m_clobbers if m_check_dangling_p, > so we only need to remove them under the same condition. > > Tested on aarch64-linux-gnu. OK to install? > > Richard > > > gcc/ > PR middle-end/104092 > * gimple-ssa-warn-access.cc (pass_waccess::update_clobbers_from_lhs): > New function, split out from... > (pass_waccess::check_stmt): ...here and generalized to calls. > (pass_waccess::check_block): Call it. > > gcc/testsuite/ > * gcc.target/aarch64/sve/acle/general/pr104092.c: New test.
I've pushed the test to trunk after Richard's EOL fix (thanks). Richard > --- > gcc/gimple-ssa-warn-access.cc | 68 +++++++++++-------- > .../aarch64/sve/acle/general/pr104092.c | 7 ++ > 2 files changed, 48 insertions(+), 27 deletions(-) > create mode 100644 > gcc/testsuite/gcc.target/aarch64/sve/acle/general/pr104092.c > > diff --git a/gcc/gimple-ssa-warn-access.cc b/gcc/gimple-ssa-warn-access.cc > index f639807a78a..25066fa6b89 100644 > --- a/gcc/gimple-ssa-warn-access.cc > +++ b/gcc/gimple-ssa-warn-access.cc > @@ -2094,6 +2094,9 @@ private: > /* Check a non-call statement. */ > void check_stmt (gimple *); > > + /* Update the clobber map based on the lhs of a statement. */ > + void update_clobbers_from_lhs (gimple *); > + > /* Check statements in a basic block. */ > void check_block (basic_block); > > @@ -4270,33 +4273,6 @@ is_auto_decl (tree x) > void > pass_waccess::check_stmt (gimple *stmt) > { > - if (m_check_dangling_p && gimple_clobber_p (stmt)) > - { > - /* Ignore clobber statemts in blocks with exceptional edges. */ > - basic_block bb = gimple_bb (stmt); > - edge e = EDGE_PRED (bb, 0); > - if (e->flags & EDGE_EH) > - return; > - > - tree var = gimple_assign_lhs (stmt); > - m_clobbers.put (var, stmt); > - return; > - } > - > - if (is_gimple_assign (stmt)) > - { > - /* Clobbered unnamed temporaries such as compound literals can be > - revived. Check for an assignment to one and remove it from > - M_CLOBBERS. */ > - tree lhs = gimple_assign_lhs (stmt); > - while (handled_component_p (lhs)) > - lhs = TREE_OPERAND (lhs, 0); > - > - if (is_auto_decl (lhs)) > - m_clobbers.remove (lhs); > - return; > - } > - > if (greturn *ret = dyn_cast <greturn *> (stmt)) > { > if (optimize && flag_isolate_erroneous_paths_dereference) > @@ -4326,6 +4302,42 @@ pass_waccess::check_stmt (gimple *stmt) > } > } > > +/* Update the clobber map based on the lhs of STMT. */ > + > +void > +pass_waccess::update_clobbers_from_lhs (gimple *stmt) > +{ > + if (gimple_clobber_p (stmt)) > + { > + /* Ignore clobber statements in blocks with exceptional edges. */ > + basic_block bb = gimple_bb (stmt); > + edge e = EDGE_PRED (bb, 0); > + if (e->flags & EDGE_EH) > + return; > + > + tree var = gimple_assign_lhs (stmt); > + m_clobbers.put (var, stmt); > + return; > + } > + > + if (is_gimple_assign (stmt) || is_gimple_call (stmt)) > + { > + /* Clobbered unnamed temporaries such as compound literals can be > + revived. Check for an assignment to one and remove it from > + M_CLOBBERS. */ > + tree lhs = gimple_get_lhs (stmt); > + if (!lhs) > + return; > + > + while (handled_component_p (lhs)) > + lhs = TREE_OPERAND (lhs, 0); > + > + if (is_auto_decl (lhs)) > + m_clobbers.remove (lhs); > + return; > + } > +} > + > /* Check basic block BB for invalid accesses. */ > > void > @@ -4340,6 +4352,8 @@ pass_waccess::check_block (basic_block bb) > check_call (call); > else > check_stmt (stmt); > + if (m_check_dangling_p) > + update_clobbers_from_lhs (stmt); > } > } > > diff --git a/gcc/testsuite/gcc.target/aarch64/sve/acle/general/pr104092.c > b/gcc/testsuite/gcc.target/aarch64/sve/acle/general/pr104092.c > new file mode 100644 > index 00000000000..c17ece7d82f > --- /dev/null > +++ b/gcc/testsuite/gcc.target/aarch64/sve/acle/general/pr104092.c > @@ -0,0 +1,7 @@ > +/* { dg-options "-O2 -Wall" } */ > + > +#include <arm_sve.h> > + > +svuint64_t bar(svbool_t pg, const uint64_t *addr) { > + return svget2(svld2_u64(pg, addr), 0); > +}