diff options
Diffstat (limited to 'gcc/gimple-fold.cc')
| -rw-r--r-- | gcc/gimple-fold.cc | 131 |
1 files changed, 131 insertions, 0 deletions
diff --git a/gcc/gimple-fold.cc b/gcc/gimple-fold.cc index 37ca085..2f64de2 100644 --- a/gcc/gimple-fold.cc +++ b/gcc/gimple-fold.cc @@ -5252,6 +5252,127 @@ gimple_fold_builtin_assume_aligned (gimple_stmt_iterator *gsi) return true; } +/* If va_list type is a simple pointer and nothing special is needed, + optimize __builtin_va_start (&ap, 0) into ap = __builtin_next_arg (0), + __builtin_va_end (&ap) out as NOP and __builtin_va_copy into a simple + pointer assignment. Returns true if a change happened. */ + +static bool +gimple_fold_builtin_stdarg (gimple_stmt_iterator *gsi, gcall *call) +{ + /* These shouldn't be folded before pass_stdarg. */ + if (!(cfun->curr_properties & PROP_last_full_fold)) + return false; + + tree callee, lhs, rhs, cfun_va_list; + bool va_list_simple_ptr; + location_t loc = gimple_location (call); + gimple *nstmt0, *nstmt; + tree tlhs, oldvdef, newvdef; + + callee = gimple_call_fndecl (call); + + cfun_va_list = targetm.fn_abi_va_list (callee); + va_list_simple_ptr = POINTER_TYPE_P (cfun_va_list) + && (TREE_TYPE (cfun_va_list) == void_type_node + || TREE_TYPE (cfun_va_list) == char_type_node); + + switch (DECL_FUNCTION_CODE (callee)) + { + case BUILT_IN_VA_START: + if (!va_list_simple_ptr + || targetm.expand_builtin_va_start != NULL + || !builtin_decl_explicit_p (BUILT_IN_NEXT_ARG)) + return false; + + if (gimple_call_num_args (call) != 2) + return false; + + lhs = gimple_call_arg (call, 0); + if (!POINTER_TYPE_P (TREE_TYPE (lhs)) + || TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (lhs))) + != TYPE_MAIN_VARIANT (cfun_va_list)) + return false; + /* Create `tlhs = __builtin_next_arg(0);`. */ + tlhs = make_ssa_name (cfun_va_list); + nstmt0 = gimple_build_call (builtin_decl_explicit (BUILT_IN_NEXT_ARG), 1, integer_zero_node); + lhs = fold_build2 (MEM_REF, cfun_va_list, lhs, build_zero_cst (TREE_TYPE (lhs))); + gimple_call_set_lhs (nstmt0, tlhs); + gimple_set_location (nstmt0, loc); + gimple_move_vops (nstmt0, call); + gsi_replace (gsi, nstmt0, false); + oldvdef = gimple_vdef (nstmt0); + newvdef = make_ssa_name (gimple_vop (cfun), nstmt0); + gimple_set_vdef (nstmt0, newvdef); + + /* Create `*lhs = tlhs;`. */ + nstmt = gimple_build_assign (lhs, tlhs); + gimple_set_location (nstmt, loc); + gimple_set_vuse (nstmt, newvdef); + gimple_set_vdef (nstmt, oldvdef); + SSA_NAME_DEF_STMT (oldvdef) = nstmt; + gsi_insert_after (gsi, nstmt, GSI_NEW_STMT); + + if (dump_file && (dump_flags & TDF_DETAILS)) + { + fprintf (dump_file, "Simplified\n "); + print_gimple_stmt (dump_file, call, 0, dump_flags); + fprintf (dump_file, "into\n "); + print_gimple_stmt (dump_file, nstmt0, 0, dump_flags); + fprintf (dump_file, " "); + print_gimple_stmt (dump_file, nstmt, 0, dump_flags); + } + return true; + + case BUILT_IN_VA_COPY: + if (!va_list_simple_ptr) + return false; + + if (gimple_call_num_args (call) != 2) + return false; + + lhs = gimple_call_arg (call, 0); + if (!POINTER_TYPE_P (TREE_TYPE (lhs)) + || TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (lhs))) + != TYPE_MAIN_VARIANT (cfun_va_list)) + return false; + rhs = gimple_call_arg (call, 1); + if (TYPE_MAIN_VARIANT (TREE_TYPE (rhs)) + != TYPE_MAIN_VARIANT (cfun_va_list)) + return false; + + lhs = fold_build2 (MEM_REF, cfun_va_list, lhs, build_zero_cst (TREE_TYPE (lhs))); + nstmt = gimple_build_assign (lhs, rhs); + gimple_set_location (nstmt, loc); + gimple_move_vops (nstmt, call); + gsi_replace (gsi, nstmt, false); + + if (dump_file && (dump_flags & TDF_DETAILS)) + { + fprintf (dump_file, "Simplified\n "); + print_gimple_stmt (dump_file, call, 0, dump_flags); + fprintf (dump_file, "into\n "); + print_gimple_stmt (dump_file, nstmt, 0, dump_flags); + } + return true; + + case BUILT_IN_VA_END: + /* No effect, so the statement will be deleted. */ + if (dump_file && (dump_flags & TDF_DETAILS)) + { + fprintf (dump_file, "Removed\n "); + print_gimple_stmt (dump_file, call, 0, dump_flags); + } + unlink_stmt_vdef (call); + release_defs (call); + gsi_replace (gsi, gimple_build_nop (), true); + return true; + + default: + gcc_unreachable (); + } +} + /* Fold the non-target builtin at *GSI and return whether any simplification was made. */ @@ -5270,6 +5391,10 @@ gimple_fold_builtin (gimple_stmt_iterator *gsi) enum built_in_function fcode = DECL_FUNCTION_CODE (callee); switch (fcode) { + case BUILT_IN_VA_START: + case BUILT_IN_VA_END: + case BUILT_IN_VA_COPY: + return gimple_fold_builtin_stdarg (gsi, stmt); case BUILT_IN_BCMP: return gimple_fold_builtin_bcmp (gsi); case BUILT_IN_BCOPY: @@ -5886,6 +6011,12 @@ gimple_fold_call (gimple_stmt_iterator *gsi, bool inplace) tree overflow = NULL_TREE; switch (gimple_call_internal_fn (stmt)) { + case IFN_ASSUME: + /* Remove .ASSUME calls during the last fold since it is no + longer needed. */ + if (cfun->curr_properties & PROP_last_full_fold) + replace_call_with_value (gsi, NULL_TREE); + break; case IFN_BUILTIN_EXPECT: result = fold_builtin_expect (gimple_location (stmt), gimple_call_arg (stmt, 0), |