| Message ID | ZaEHikflGhduPrnv@tucnak |
|---|---|
| State | New |
| Headers | show |
| Series | lower-bitint: Fix up handling of uninitialized large/huge _BitInt call arguments [PR113316] | expand |
On Fri, 12 Jan 2024, Jakub Jelinek wrote: > Hi! > > The code to assign large/huge _BitInt SSA_NAMEs to partitions intentionally > ignores uninitialized SSA_NAMEs: > /* Also ignore uninitialized uses. */ > if (SSA_NAME_IS_DEFAULT_DEF (s) > && (!SSA_NAME_VAR (s) || VAR_P (SSA_NAME_VAR (s)))) > continue; > because there is no need to store them into memory, all we need is when > trying to extract some limb from them use uninitialized SSA_NAME for the > limb. > > The following testcase shows this is a problem for call arguments though, > for those we need to create replacement SSA_NAMEs which are loaded from > the underlying variable. For uninitialized SSA_NAMEs because we didn't > create underlying variable for them var_to_partition doesn't work, the > following patch handles it by just creating an uninitialized replacement > SSA_NAME. > > Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk? OK > 2024-01-12 Jakub Jelinek <jakub@redhat.com> > > PR tree-optimization/113316 > * gimple-lower-bitint.cc (bitint_large_huge::lower_call): Handle > uninitialized large/huge _BitInt arguments to calls. > > * gcc.dg/bitint-67.c: New test. > > --- gcc/gimple-lower-bitint.cc.jj 2024-01-11 11:46:49.147779946 +0100 > +++ gcc/gimple-lower-bitint.cc 2024-01-11 13:52:46.106182653 +0100 > @@ -5118,14 +5118,23 @@ bitint_large_huge::lower_call (tree obj, > || TREE_CODE (TREE_TYPE (arg)) != BITINT_TYPE > || bitint_precision_kind (TREE_TYPE (arg)) <= bitint_prec_middle) > continue; > - int p = var_to_partition (m_map, arg); > - tree v = m_vars[p]; > - gcc_assert (v != NULL_TREE); > - if (!types_compatible_p (TREE_TYPE (arg), TREE_TYPE (v))) > - v = build1 (VIEW_CONVERT_EXPR, TREE_TYPE (arg), v); > - arg = make_ssa_name (TREE_TYPE (arg)); > - gimple *g = gimple_build_assign (arg, v); > - gsi_insert_before (&gsi, g, GSI_SAME_STMT); > + if (SSA_NAME_IS_DEFAULT_DEF (arg) > + && (!SSA_NAME_VAR (arg) || VAR_P (SSA_NAME_VAR (arg)))) > + { > + tree var = create_tmp_reg (TREE_TYPE (arg)); > + arg = get_or_create_ssa_default_def (cfun, var); > + } > + else > + { > + int p = var_to_partition (m_map, arg); > + tree v = m_vars[p]; > + gcc_assert (v != NULL_TREE); > + if (!types_compatible_p (TREE_TYPE (arg), TREE_TYPE (v))) > + v = build1 (VIEW_CONVERT_EXPR, TREE_TYPE (arg), v); > + arg = make_ssa_name (TREE_TYPE (arg)); > + gimple *g = gimple_build_assign (arg, v); > + gsi_insert_before (&gsi, g, GSI_SAME_STMT); > + } > gimple_call_set_arg (stmt, i, arg); > if (m_preserved == NULL) > m_preserved = BITMAP_ALLOC (NULL); > --- gcc/testsuite/gcc.dg/bitint-67.c.jj 2024-01-11 13:54:14.561936065 +0100 > +++ gcc/testsuite/gcc.dg/bitint-67.c 2024-01-11 13:55:09.474162196 +0100 > @@ -0,0 +1,12 @@ > +/* PR tree-optimization/113316 */ > +/* { dg-do compile { target bitint575 } } */ > +/* { dg-options "-std=c23 -O2 -w" } */ > + > +void bar (_BitInt(535) y); > + > +void > +foo (void) > +{ > + _BitInt(535) y; > + bar (y); > +} > > Jakub > >
--- gcc/gimple-lower-bitint.cc.jj 2024-01-11 11:46:49.147779946 +0100 +++ gcc/gimple-lower-bitint.cc 2024-01-11 13:52:46.106182653 +0100 @@ -5118,14 +5118,23 @@ bitint_large_huge::lower_call (tree obj, || TREE_CODE (TREE_TYPE (arg)) != BITINT_TYPE || bitint_precision_kind (TREE_TYPE (arg)) <= bitint_prec_middle) continue; - int p = var_to_partition (m_map, arg); - tree v = m_vars[p]; - gcc_assert (v != NULL_TREE); - if (!types_compatible_p (TREE_TYPE (arg), TREE_TYPE (v))) - v = build1 (VIEW_CONVERT_EXPR, TREE_TYPE (arg), v); - arg = make_ssa_name (TREE_TYPE (arg)); - gimple *g = gimple_build_assign (arg, v); - gsi_insert_before (&gsi, g, GSI_SAME_STMT); + if (SSA_NAME_IS_DEFAULT_DEF (arg) + && (!SSA_NAME_VAR (arg) || VAR_P (SSA_NAME_VAR (arg)))) + { + tree var = create_tmp_reg (TREE_TYPE (arg)); + arg = get_or_create_ssa_default_def (cfun, var); + } + else + { + int p = var_to_partition (m_map, arg); + tree v = m_vars[p]; + gcc_assert (v != NULL_TREE); + if (!types_compatible_p (TREE_TYPE (arg), TREE_TYPE (v))) + v = build1 (VIEW_CONVERT_EXPR, TREE_TYPE (arg), v); + arg = make_ssa_name (TREE_TYPE (arg)); + gimple *g = gimple_build_assign (arg, v); + gsi_insert_before (&gsi, g, GSI_SAME_STMT); + } gimple_call_set_arg (stmt, i, arg); if (m_preserved == NULL) m_preserved = BITMAP_ALLOC (NULL); --- gcc/testsuite/gcc.dg/bitint-67.c.jj 2024-01-11 13:54:14.561936065 +0100 +++ gcc/testsuite/gcc.dg/bitint-67.c 2024-01-11 13:55:09.474162196 +0100 @@ -0,0 +1,12 @@ +/* PR tree-optimization/113316 */ +/* { dg-do compile { target bitint575 } } */ +/* { dg-options "-std=c23 -O2 -w" } */ + +void bar (_BitInt(535) y); + +void +foo (void) +{ + _BitInt(535) y; + bar (y); +}
Hi! The code to assign large/huge _BitInt SSA_NAMEs to partitions intentionally ignores uninitialized SSA_NAMEs: /* Also ignore uninitialized uses. */ if (SSA_NAME_IS_DEFAULT_DEF (s) && (!SSA_NAME_VAR (s) || VAR_P (SSA_NAME_VAR (s)))) continue; because there is no need to store them into memory, all we need is when trying to extract some limb from them use uninitialized SSA_NAME for the limb. The following testcase shows this is a problem for call arguments though, for those we need to create replacement SSA_NAMEs which are loaded from the underlying variable. For uninitialized SSA_NAMEs because we didn't create underlying variable for them var_to_partition doesn't work, the following patch handles it by just creating an uninitialized replacement SSA_NAME. Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk? 2024-01-12 Jakub Jelinek <jakub@redhat.com> PR tree-optimization/113316 * gimple-lower-bitint.cc (bitint_large_huge::lower_call): Handle uninitialized large/huge _BitInt arguments to calls. * gcc.dg/bitint-67.c: New test. Jakub