Hello! > This patch implements what I understood from Joseph's > https://gcc.gnu.org/ml/gcc/2013-10/msg00280.html > and also adds clang compatible builtins (which implement > small subset of the typegeneric ones). > > Besides the clang compatibility builtins, there are 3 new > type-generic builtins, __builtin_{add,sub,mul}_overflow, which > have 3 arguments, two arbitrary integral arguments, and pointer > to some integer type. These builtins extend both arguments > to infinite precision signed arguments, perform {+,-,*} operations > in the infinite precision and finally cast the result to the type > pointed by the third argument and store the result there (modulo > 2^precision of the type). If the infinite precision result is equal > to the stored value, the built-ins return false (no overflow), otherwise > they return true. > > The built-ins are folded immediately into internal functions that return > both results (integer result and boolean overflow flag) as _Complex integer > result, so that the integer result doesn't have to be addressable. > It partly reuses code to emit -fsanitize=signed-integer-overflow internal > functions, for signed overflows on e.g. i?86 will use jo/jno/seto/setno > instructions after the arithmetic instructions; for imsogmed arithmetic > overflow, combiner manages to transform what is emitted into > jc/jnc/setc/setnc where possible. > > After discussions with Richard on IRC, the internal functions have > arbitrary integral arguments, which can have different or same signs, > different or same precisions, and the result type is _Complex integer > derived from the call's third argument. gimple-fold.c and tree-vrp.c > is tought to perform some optimizations on these, and most of the smarts > are performed during expansion (many of the 16 different +/- > signarg1/signarg2/signresult cases require different code, and for * > there are also a couple of different cases). > If somebody can come up with some shorter sequence how to test for the > less common cases, I'd appreciate hints (internal-fn.c has big comments > which explain how it now computes the integral result and especially > the overflow flag). > > Bootstrapped/regtested on x86_64-linux and i686-linux (on top of the ICF > gimple_call fix I've mailed a few minutes ago), ok for trunk? > > 2014-11-10 Jakub Jelinek <ja...@redhat.com> > > PR c/59708 > * builtin-attrs.def (ATTR_NOTHROW_TYPEGENERIC_LEAF): New attribute. > * builtins.c (fold_builtin_arith_overflow): New function. > (fold_builtin_3): Use it. > * builtins.def (BUILT_IN_ADD_OVERFLOW, BUILT_IN_SUB_OVERFLOW, > BUILT_IN_MUL_OVERFLOW, BUILT_IN_SADD_OVERFLOW, > BUILT_IN_SADDL_OVERFLOW, BUILT_IN_SADDLL_OVERFLOW, > BUILT_IN_SSUB_OVERFLOW, BUILT_IN_SSUBL_OVERFLOW, > BUILT_IN_SSUBLL_OVERFLOW, BUILT_IN_SMUL_OVERFLOW, > BUILT_IN_SMULL_OVERFLOW, BUILT_IN_SMULLL_OVERFLOW, > BUILT_IN_UADDL_OVERFLOW, BUILT_IN_UADDLL_OVERFLOW, > BUILT_IN_USUB_OVERFLOW, BUILT_IN_USUBL_OVERFLOW, > BUILT_IN_USUBLL_OVERFLOW, BUILT_IN_UMUL_OVERFLOW, > BUILT_IN_UMULL_OVERFLOW, BUILT_IN_UMULLL_OVERFLOW): New built-in functions. > * builtin-types.def (BT_PTR_UINT, BT_PTR_ULONG, BT_PTR_LONGLONG, > BT_FN_BOOL_INT_INT_INTPTR, BT_FN_BOOL_LONG_LONG_LONGPTR, > BT_FN_BOOL_LONGLONG_LONGLONG_LONGLONGPTR, > BT_FN_BOOL_UINT_UINT_UINTPTR, BT_FN_BOOL_ULONG_ULONG_ULONGPTR, > BT_FN_BOOL_ULONGLONG_ULONGLONG_ULONGLONGPTR, BT_FN_BOOL_VAR): New. > * expr.c (write_complex_part): Remove prototype, no longer static. > * expr.h (write_complex_part): New prototype. > * function.c (aggregate_value_p): For internal functions return 0. > * gimple-fold.c (arith_overflowed_p, find_non_realpart_uses): New functions. > (gimple_fold_call): Fold {ADD,SUB,MUL}_OVERFLOW internal calls. > * gimple-fold.h (arith_overflowed_p): New prototype. > * gimplify.c (gimplify_call_expr): Handle gimplification of internal calls > with lhs. > * internal-fn.c (get_range_pos_neg, get_min_precision, > expand_arith_overflow_result_store): New functions. > (ubsan_expand_si_overflow_addsub_check): Renamed to ... > (expand_addsub_overflow): ... this. Add LOC, LHS, ARG0, ARG1, > UNSR_P, UNS0_P, UNS1_P, IS_UBSAN arguments, remove STMT argument. > Handle ADD_OVERFLOW and SUB_OVERFLOW expansion. > (ubsan_expand_si_overflow_neg_check): Renamed to ... > (expand_neg_overflow): ... this. Add LOC, LHS, ARG1, IS_UBSAN > arguments, remove STMT argument. Handle SUB_OVERFLOW with > 0 as first argument expansion. > (ubsan_expand_si_overflow_mul_check): Renamed to ... > (expand_mul_overflow): ... this. Add LOC, LHS, ARG0, ARG1, > UNSR_P, UNS0_P, UNS1_P, IS_UBSAN arguments, remove STMT argument. > Handle MUL_OVERFLOW expansion. > (expand_UBSAN_CHECK_ADD): Use expand_addsub_overflow, prepare > arguments for it. > (expand_UBSAN_CHECK_SUB): Use expand_addsub_overflow or > expand_neg_overflow, prepare arguments for it. > (expand_UBSAN_CHECK_MUL): Use expand_mul_overflow, prepare arguments > for it. > (expand_arith_overflow, expand_ADD_OVERFLOW, expand_SUB_OVERFLOW, > expand_MUL_OVERFLOW): New functions. > * internal-fn.def (ADD_OVERFLOW, SUB_OVERFLOW, MUL_OVERFLOW): New > internal functions. > * tree-vrp.c (check_for_binary_op_overflow): New function. > (extract_range_basic): Handle {REAL,IMAG}PART_EXPR if the operand > is SSA_NAME set by {ADD,SUB,MUL}_OVERFLOW internal functions. > (simplify_internal_call_using_ranges): Handle {ADD,SUB,MUL}_OVERFLOW > internal functions. > * optabs.def (umulv4_optab): New optab. > * config/i386/i386.md (umulv<mode>4, <u>mulvqi4): New define_expands. > (*umulv<mode>4, *<u>mulvqi4): New define_insns. > * doc/extend.texi (Integer Overflow Builtins): Document > __builtin_*_overflow. > c-family/ > * c-common.c (check_builtin_function_arguments): Handle > BUILT_IN_{ADD,SUB,MUL}_OVERFLOW. > testsuite/ > * c-c++-common/builtin-arith-overflow-1.c: New test. > * c-c++-common/torture/builtin-arith-overflow-10.c: New test. > * c-c++-common/torture/builtin-arith-overflow-11.c: New test. > * c-c++-common/torture/builtin-arith-overflow-12.c: New test. > * c-c++-common/torture/builtin-arith-overflow-12.h: New file. > * c-c++-common/torture/builtin-arith-overflow-13.c: New test. > * c-c++-common/torture/builtin-arith-overflow-14.c: New test. > * c-c++-common/torture/builtin-arith-overflow-15.c: New test. > * c-c++-common/torture/builtin-arith-overflow-16.c: New test. > * c-c++-common/torture/builtin-arith-overflow-17.c: New test. > * c-c++-common/torture/builtin-arith-overflow-18.c: New test. > * c-c++-common/torture/builtin-arith-overflow-1.c: New test. > * c-c++-common/torture/builtin-arith-overflow-1.h: New file. > * c-c++-common/torture/builtin-arith-overflow-2.c: New test. > * c-c++-common/torture/builtin-arith-overflow-3.c: New test. > * c-c++-common/torture/builtin-arith-overflow-4.c: New test. > * c-c++-common/torture/builtin-arith-overflow-5.c: New test. > * c-c++-common/torture/builtin-arith-overflow-6.c: New test. > * c-c++-common/torture/builtin-arith-overflow-7.c: New test. > * c-c++-common/torture/builtin-arith-overflow-8.c: New test. > * c-c++-common/torture/builtin-arith-overflow-9.c: New test. > * c-c++-common/torture/builtin-arith-overflow.h: New file. > * gcc.dg/builtin-arith-overflow-1.c: New test. > * gcc.dg/builtin-arith-overflow-2.c: New test.
x86 part is OK. Thanks, Uros.
