diff options
Diffstat (limited to 'gcc/builtins.c')
| -rw-r--r-- | gcc/builtins.c | 54 |
1 files changed, 51 insertions, 3 deletions
diff --git a/gcc/builtins.c b/gcc/builtins.c index d519176..5d234a5 100644 --- a/gcc/builtins.c +++ b/gcc/builtins.c @@ -64,6 +64,7 @@ along with GCC; see the file COPYING3. If not see #include "rtl-chkp.h" #include "internal-fn.h" #include "case-cfn-macros.h" +#include "gimple-fold.h" struct target_builtins default_target_builtins; @@ -7943,18 +7944,28 @@ fold_builtin_unordered_cmp (location_t loc, tree fndecl, tree arg0, tree arg1, /* Fold __builtin_{,s,u}{add,sub,mul}{,l,ll}_overflow, either into normal arithmetics if it can never overflow, or into internal functions that return both result of arithmetics and overflowed boolean flag in - a complex integer result, or some other check for overflow. */ + a complex integer result, or some other check for overflow. + Similarly fold __builtin_{add,sub,mul}_overflow_p to just the overflow + checking part of that. */ static tree fold_builtin_arith_overflow (location_t loc, enum built_in_function fcode, tree arg0, tree arg1, tree arg2) { enum internal_fn ifn = IFN_LAST; - tree type = TREE_TYPE (TREE_TYPE (arg2)); - tree mem_arg2 = build_fold_indirect_ref_loc (loc, arg2); + /* The code of the expression corresponding to the type-generic + built-in, or ERROR_MARK for the type-specific ones. */ + enum tree_code opcode = ERROR_MARK; + bool ovf_only = false; + switch (fcode) { + case BUILT_IN_ADD_OVERFLOW_P: + ovf_only = true; + /* FALLTHRU */ case BUILT_IN_ADD_OVERFLOW: + opcode = PLUS_EXPR; + /* FALLTHRU */ case BUILT_IN_SADD_OVERFLOW: case BUILT_IN_SADDL_OVERFLOW: case BUILT_IN_SADDLL_OVERFLOW: @@ -7963,7 +7974,12 @@ fold_builtin_arith_overflow (location_t loc, enum built_in_function fcode, case BUILT_IN_UADDLL_OVERFLOW: ifn = IFN_ADD_OVERFLOW; break; + case BUILT_IN_SUB_OVERFLOW_P: + ovf_only = true; + /* FALLTHRU */ case BUILT_IN_SUB_OVERFLOW: + opcode = MINUS_EXPR; + /* FALLTHRU */ case BUILT_IN_SSUB_OVERFLOW: case BUILT_IN_SSUBL_OVERFLOW: case BUILT_IN_SSUBLL_OVERFLOW: @@ -7972,7 +7988,12 @@ fold_builtin_arith_overflow (location_t loc, enum built_in_function fcode, case BUILT_IN_USUBLL_OVERFLOW: ifn = IFN_SUB_OVERFLOW; break; + case BUILT_IN_MUL_OVERFLOW_P: + ovf_only = true; + /* FALLTHRU */ case BUILT_IN_MUL_OVERFLOW: + opcode = MULT_EXPR; + /* FALLTHRU */ case BUILT_IN_SMUL_OVERFLOW: case BUILT_IN_SMULL_OVERFLOW: case BUILT_IN_SMULLL_OVERFLOW: @@ -7984,6 +8005,25 @@ fold_builtin_arith_overflow (location_t loc, enum built_in_function fcode, default: gcc_unreachable (); } + + /* For the "generic" overloads, the first two arguments can have different + types and the last argument determines the target type to use to check + for overflow. The arguments of the other overloads all have the same + type. */ + tree type = ovf_only ? TREE_TYPE (arg2) : TREE_TYPE (TREE_TYPE (arg2)); + + /* For the __builtin_{add,sub,mul}_overflow_p builtins, when the first two + arguments are constant, attempt to fold the built-in call into a constant + expression indicating whether or not it detected an overflow. */ + if (ovf_only + && TREE_CODE (arg0) == INTEGER_CST + && TREE_CODE (arg1) == INTEGER_CST) + /* Perform the computation in the target type and check for overflow. */ + return omit_one_operand_loc (loc, boolean_type_node, + arith_overflowed_p (opcode, type, arg0, arg1) + ? boolean_true_node : boolean_false_node, + arg2); + tree ctype = build_complex_type (type); tree call = build_call_expr_internal_loc (loc, ifn, ctype, 2, arg0, arg1); @@ -7991,6 +8031,11 @@ fold_builtin_arith_overflow (location_t loc, enum built_in_function fcode, tree intres = build1_loc (loc, REALPART_EXPR, type, tgt); tree ovfres = build1_loc (loc, IMAGPART_EXPR, type, tgt); ovfres = fold_convert_loc (loc, boolean_type_node, ovfres); + + if (ovf_only) + return omit_one_operand_loc (loc, boolean_type_node, ovfres, arg2); + + tree mem_arg2 = build_fold_indirect_ref_loc (loc, arg2); tree store = fold_build2_loc (loc, MODIFY_EXPR, void_type_node, mem_arg2, intres); return build2_loc (loc, COMPOUND_EXPR, boolean_type_node, store, ovfres); @@ -8340,6 +8385,9 @@ fold_builtin_3 (location_t loc, tree fndecl, case BUILT_IN_ADD_OVERFLOW: case BUILT_IN_SUB_OVERFLOW: case BUILT_IN_MUL_OVERFLOW: + case BUILT_IN_ADD_OVERFLOW_P: + case BUILT_IN_SUB_OVERFLOW_P: + case BUILT_IN_MUL_OVERFLOW_P: case BUILT_IN_SADD_OVERFLOW: case BUILT_IN_SADDL_OVERFLOW: case BUILT_IN_SADDLL_OVERFLOW: |