| Message ID | 20111202192848.GH27242@tyan-ft48-01.lab.bos.redhat.com |
|---|---|
| State | New |
| Headers | show |
On Fri, Dec 2, 2011 at 8:28 PM, Jakub Jelinek <jakub@redhat.com> wrote: > On Fri, Dec 02, 2011 at 02:27:40PM +0100, Richard Guenther wrote: >> This change seems wrong. We are turning valid gimple >> >> # DEBUG D#2 => transfer.0 [with addres taken] >> >> into invalid one >> >> # DEBUG D#2 => transfer.0 [without address taken] >> >> once you update that stmt with update_stmt you'll get an SSA operand >> for transfer.0 which is not in SSA form because you fail to rewrite it >> into. >> >> Why do this in remove_unused_locals and not in update_address_taken? >> Or, why do it at all? >> >> I have a SSA operand checking patch that catches this now ... > > Here is a fix for that. Instead of clearing TREE_ADDRESSABLE for > unreferenced vars we allow them in target_for_debug_bind if they aren't > referenced vars (thus we don't risk mixing VALUE tracking with the > old style REG_EXPR/MEM_EXPR tracking of these variables). > > Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk? Ok. (Note that the outcome of target_for_debug_bind may change during compilation, but only from false to true as far as I can see, so that should be ok) Thanks, Richard. > 2011-12-02 Jakub Jelinek <jakub@redhat.com> > > PR debug/50317 > * tree-ssa.c (target_for_debug_bind): Also allow is_gimple_reg_type > vars that aren't referenced. > (tree-ssa-live.c (remove_unused_locals): Don't clear TREE_ADDRESSABLE > of unreferenced local vars. > * cfgexpand.c (expand_debug_expr): For DEBUG_IMPLICIT_PTR allow also > TREE_ADDRESSABLE vars that satisfy target_for_debug_bind. > > --- gcc/tree-ssa.c.jj 2011-11-29 08:58:52.000000000 +0100 > +++ gcc/tree-ssa.c 2011-12-02 15:04:03.494148642 +0100 > @@ -264,7 +264,12 @@ target_for_debug_bind (tree var) > return NULL_TREE; > > if (!is_gimple_reg (var)) > - return NULL_TREE; > + { > + if (is_gimple_reg_type (TREE_TYPE (var)) > + && referenced_var_lookup (cfun, DECL_UID (var)) == NULL_TREE) > + return var; > + return NULL_TREE; > + } > > return var; > } > --- gcc/tree-ssa-live.c.jj 2011-12-02 01:52:27.000000000 +0100 > +++ gcc/tree-ssa-live.c 2011-12-02 15:04:59.601816335 +0100 > @@ -814,15 +814,7 @@ remove_unused_locals (void) > bitmap_set_bit (global_unused_vars, DECL_UID (var)); > } > else > - { > - /* For unreferenced local vars drop TREE_ADDRESSABLE > - bit in case it is referenced from debug stmts. */ > - if (DECL_CONTEXT (var) == current_function_decl > - && TREE_ADDRESSABLE (var) > - && is_gimple_reg_type (TREE_TYPE (var))) > - TREE_ADDRESSABLE (var) = 0; > - continue; > - } > + continue; > } > else if (TREE_CODE (var) == VAR_DECL > && DECL_HARD_REGISTER (var) > --- gcc/cfgexpand.c.jj 2011-12-02 01:52:27.000000000 +0100 > +++ gcc/cfgexpand.c 2011-12-02 15:24:37.982327507 +0100 > @@ -3325,7 +3325,8 @@ expand_debug_expr (tree exp) > if ((TREE_CODE (TREE_OPERAND (exp, 0)) == VAR_DECL > || TREE_CODE (TREE_OPERAND (exp, 0)) == PARM_DECL > || TREE_CODE (TREE_OPERAND (exp, 0)) == RESULT_DECL) > - && !TREE_ADDRESSABLE (TREE_OPERAND (exp, 0))) > + && (!TREE_ADDRESSABLE (TREE_OPERAND (exp, 0)) > + || target_for_debug_bind (TREE_OPERAND (exp, 0)))) > return gen_rtx_DEBUG_IMPLICIT_PTR (mode, TREE_OPERAND (exp, 0)); > > if (handled_component_p (TREE_OPERAND (exp, 0))) > @@ -3337,7 +3338,8 @@ expand_debug_expr (tree exp) > if ((TREE_CODE (decl) == VAR_DECL > || TREE_CODE (decl) == PARM_DECL > || TREE_CODE (decl) == RESULT_DECL) > - && !TREE_ADDRESSABLE (decl) > + && (!TREE_ADDRESSABLE (decl) > + || target_for_debug_bind (decl)) > && (bitoffset % BITS_PER_UNIT) == 0 > && bitsize > 0 > && bitsize == maxsize) > > > Jakub
--- gcc/tree-ssa.c.jj 2011-11-29 08:58:52.000000000 +0100 +++ gcc/tree-ssa.c 2011-12-02 15:04:03.494148642 +0100 @@ -264,7 +264,12 @@ target_for_debug_bind (tree var) return NULL_TREE; if (!is_gimple_reg (var)) - return NULL_TREE; + { + if (is_gimple_reg_type (TREE_TYPE (var)) + && referenced_var_lookup (cfun, DECL_UID (var)) == NULL_TREE) + return var; + return NULL_TREE; + } return var; } --- gcc/tree-ssa-live.c.jj 2011-12-02 01:52:27.000000000 +0100 +++ gcc/tree-ssa-live.c 2011-12-02 15:04:59.601816335 +0100 @@ -814,15 +814,7 @@ remove_unused_locals (void) bitmap_set_bit (global_unused_vars, DECL_UID (var)); } else - { - /* For unreferenced local vars drop TREE_ADDRESSABLE - bit in case it is referenced from debug stmts. */ - if (DECL_CONTEXT (var) == current_function_decl - && TREE_ADDRESSABLE (var) - && is_gimple_reg_type (TREE_TYPE (var))) - TREE_ADDRESSABLE (var) = 0; - continue; - } + continue; } else if (TREE_CODE (var) == VAR_DECL && DECL_HARD_REGISTER (var) --- gcc/cfgexpand.c.jj 2011-12-02 01:52:27.000000000 +0100 +++ gcc/cfgexpand.c 2011-12-02 15:24:37.982327507 +0100 @@ -3325,7 +3325,8 @@ expand_debug_expr (tree exp) if ((TREE_CODE (TREE_OPERAND (exp, 0)) == VAR_DECL || TREE_CODE (TREE_OPERAND (exp, 0)) == PARM_DECL || TREE_CODE (TREE_OPERAND (exp, 0)) == RESULT_DECL) - && !TREE_ADDRESSABLE (TREE_OPERAND (exp, 0))) + && (!TREE_ADDRESSABLE (TREE_OPERAND (exp, 0)) + || target_for_debug_bind (TREE_OPERAND (exp, 0)))) return gen_rtx_DEBUG_IMPLICIT_PTR (mode, TREE_OPERAND (exp, 0)); if (handled_component_p (TREE_OPERAND (exp, 0))) @@ -3337,7 +3338,8 @@ expand_debug_expr (tree exp) if ((TREE_CODE (decl) == VAR_DECL || TREE_CODE (decl) == PARM_DECL || TREE_CODE (decl) == RESULT_DECL) - && !TREE_ADDRESSABLE (decl) + && (!TREE_ADDRESSABLE (decl) + || target_for_debug_bind (decl)) && (bitoffset % BITS_PER_UNIT) == 0 && bitsize > 0 && bitsize == maxsize)