Hi! The following testcase ICEs, because we call tree_function_versioning from old_decl which has target attributes not supporting V4DImode and so DECL_MODE of DECL_ARGUMENTS is BLKmode, while new_decl supports those. tree_function_versioning initially copies DECL_RESULT and DECL_ARGUMENTS from old_decl to new_decl, then calls initialize_cfun to create cfun and only when the cfun is created it can later actually remap_decl DECL_RESULT and DECL_ARGUMENTS etc. The problem is that initialize_cfun -> push_struct_function -> allocate_struct_function calls relayout_decl on DECL_RESULT and DECL_ARGUMENTS, which clobbers DECL_MODE of old_decl and we then ICE because of it. In particular, allocate_struct_function does: if (!abstract_p) { /* Now that we have activated any function-specific attributes that might affect layout, particularly vector modes, relayout each of the parameters and the result. */ relayout_decl (result); for (tree parm = DECL_ARGUMENTS (fndecl); parm; parm = DECL_CHAIN (parm)) relayout_decl (parm);
/* Similarly relayout the function decl. */ targetm.target_option.relayout_function (fndecl); } if (!abstract_p && aggregate_value_p (result, fndecl)) { #ifdef PCC_STATIC_STRUCT_RETURN cfun->returns_pcc_struct = 1; #endif cfun->returns_struct = 1; } Now, in the case of tree_function_versioning, I believe all that we need from these is possibly the targetm.target_option.relayout_function (fndecl); call (arm only), we will remap DECL_RESULT and DECL_ARGUMENTS later on and copy_decl_for_dup_finish in that case will handle all we need: /* For vector typed decls make sure to update DECL_MODE according to the new function context. */ if (VECTOR_TYPE_P (TREE_TYPE (copy))) SET_DECL_MODE (copy, TYPE_MODE (TREE_TYPE (copy))); We don't need the cfun->returns_*struct either, because we override it in initialize_cfun a few lines later: /* Copy items we preserve during cloning. */ ... cfun->returns_struct = src_cfun->returns_struct; cfun->returns_pcc_struct = src_cfun->returns_pcc_struct; So, to avoid the clobbering of DECL_RESULT/DECL_ARGUMENTS of old_decl, the following patch arranges allocate_struct_function to be called with abstract_p true and calls targetm.target_option.relayout_function (fndecl); by hand. The removal of DECL_RESULT/DECL_ARGUMENTS copying at the start of initialize_cfun is removed because the only caller - tree_function_versioning, does that unconditionally before. Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk? 2023-03-17 Jakub Jelinek <ja...@redhat.com> PR target/105554 * function.h (push_struct_function): Add ABSTRACT_P argument defaulted to false. * function.cc (push_struct_function): Add ABSTRACT_P argument, pass it to allocate_struct_function instead of false. * tree-inline.cc (initialize_cfun): Don't copy DECL_ARGUMENTS nor DECL_RESULT here. Pass true as ABSTRACT_P to push_struct_function. Call targetm.target_option.relayout_function after it. (tree_function_versioning): Formatting fix. * gcc.target/i386/pr105554.c: New test. --- gcc/function.h.jj 2023-01-12 21:04:08.647239183 +0100 +++ gcc/function.h 2023-03-17 10:47:27.489571469 +0100 @@ -687,7 +687,7 @@ extern void pop_cfun (void); extern int get_next_funcdef_no (void); extern int get_last_funcdef_no (void); extern void allocate_struct_function (tree, bool); -extern void push_struct_function (tree fndecl); +extern void push_struct_function (tree fndecl, bool = false); extern void push_dummy_function (bool); extern void pop_dummy_function (void); extern void init_dummy_function_start (void); --- gcc/function.cc.jj 2023-01-14 10:00:20.308560059 +0100 +++ gcc/function.cc 2023-03-17 10:48:10.009945483 +0100 @@ -4891,7 +4891,7 @@ allocate_struct_function (tree fndecl, b instead of just setting it. */ void -push_struct_function (tree fndecl) +push_struct_function (tree fndecl, bool abstract_p) { /* When in_dummy_function we might be in the middle of a pop_cfun and current_function_decl and cfun may not match. */ @@ -4900,7 +4900,7 @@ push_struct_function (tree fndecl) || (cfun && current_function_decl == cfun->decl)); cfun_stack.safe_push (cfun); current_function_decl = fndecl; - allocate_struct_function (fndecl, false); + allocate_struct_function (fndecl, abstract_p); } /* Reset crtl and other non-struct-function variables to defaults as --- gcc/tree-inline.cc.jj 2023-01-19 09:58:51.037226790 +0100 +++ gcc/tree-inline.cc 2023-03-17 10:56:50.321285330 +0100 @@ -2781,16 +2781,12 @@ initialize_cfun (tree new_fndecl, tree c { struct function *src_cfun = DECL_STRUCT_FUNCTION (callee_fndecl); - if (!DECL_ARGUMENTS (new_fndecl)) - DECL_ARGUMENTS (new_fndecl) = DECL_ARGUMENTS (callee_fndecl); - if (!DECL_RESULT (new_fndecl)) - DECL_RESULT (new_fndecl) = DECL_RESULT (callee_fndecl); - /* Register specific tree functions. */ gimple_register_cfg_hooks (); /* Get clean struct function. */ - push_struct_function (new_fndecl); + push_struct_function (new_fndecl, true); + targetm.target_option.relayout_function (new_fndecl); /* We will rebuild these, so just sanity check that they are empty. */ gcc_assert (VALUE_HISTOGRAMS (cfun) == NULL); @@ -6235,8 +6231,7 @@ tree_function_versioning (tree old_decl, id.transform_return_to_modify = false; id.transform_parameter = false; - old_entry_block = ENTRY_BLOCK_PTR_FOR_FN - (DECL_STRUCT_FUNCTION (old_decl)); + old_entry_block = ENTRY_BLOCK_PTR_FOR_FN (DECL_STRUCT_FUNCTION (old_decl)); DECL_RESULT (new_decl) = DECL_RESULT (old_decl); DECL_ARGUMENTS (new_decl) = DECL_ARGUMENTS (old_decl); initialize_cfun (new_decl, old_decl, --- gcc/testsuite/gcc.target/i386/pr105554.c.jj 2023-03-17 10:11:38.998223934 +0100 +++ gcc/testsuite/gcc.target/i386/pr105554.c 2023-03-17 10:11:38.998223934 +0100 @@ -0,0 +1,10 @@ +/* PR target/105554 */ +/* { dg-do compile } */ +/* { dg-options "-O2 -Wno-psabi -mno-sse3" } */ + +typedef long long v4di __attribute__((__vector_size__(32))); + +__attribute__((target_clones ("arch=core-avx2", "default"))) void +foo (v4di x) +{ +} Jakub