commit 4e65a17e62c7c2f3c0409d9769cca2e916a88379 Author: Andreas Arnez Date: Mon Apr 27 11:38:47 2015 +0200 S390: Re-arrange implementation of s390_return_value Move related logic in the implementation of s390_return_value closer together. This makes it easier to read and extend. gdb/ChangeLog: * s390-linux-tdep.c (s390_return_value_convention): Remove function. Inline its logic... (s390_return_value): ...here. Instead, move the handling of the "register" return value convention... (s390_register_return_value): ...here. New function. ### a/gdb/ChangeLog ### b/gdb/ChangeLog ## -1,5 +1,13 @@ 2015-04-27 Andreas Arnez + * s390-linux-tdep.c (s390_return_value_convention): Remove + function. Inline its logic... + (s390_return_value): ...here. Instead, move the handling of the + "register" return value convention... + (s390_register_return_value): ...here. New function. + +2015-04-27 Andreas Arnez + * s390-linux-tdep.c (is_float_singleton): Remove function. Move the "singleton" part of the logic... Index: gdb-7.6.1/gdb/s390-tdep.c =================================================================== --- gdb-7.6.1.orig/gdb/s390-tdep.c 2016-02-21 22:31:47.311935241 +0100 +++ gdb-7.6.1/gdb/s390-tdep.c 2016-02-21 22:31:59.326029901 +0100 @@ -2865,110 +2865,98 @@ } -/* Function return value access. */ +/* Helper for s390_return_value: Set or retrieve a function return + value if it resides in a register. */ -static enum return_value_convention -s390_return_value_convention (struct gdbarch *gdbarch, struct type *type) +static void +s390_register_return_value (struct gdbarch *gdbarch, struct type *type, + struct regcache *regcache, + gdb_byte *out, const gdb_byte *in) { - if (TYPE_LENGTH (type) > 8) - return RETURN_VALUE_STRUCT_CONVENTION; + enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); + int word_size = gdbarch_ptr_bit (gdbarch) / 8; + int length = TYPE_LENGTH (type); + int code = TYPE_CODE (type); - switch (TYPE_CODE (type)) + if (code == TYPE_CODE_FLT || code == TYPE_CODE_DECFLOAT) { - case TYPE_CODE_STRUCT: - case TYPE_CODE_UNION: - case TYPE_CODE_ARRAY: - case TYPE_CODE_COMPLEX: - return RETURN_VALUE_STRUCT_CONVENTION; - - default: - return RETURN_VALUE_REGISTER_CONVENTION; + /* Float-like value: left-aligned in f0. */ + if (in != NULL) + regcache_cooked_write_part (regcache, S390_F0_REGNUM, + 0, length, in); + else + regcache_cooked_read_part (regcache, S390_F0_REGNUM, + 0, length, out); + } + else if (length <= word_size) + { + /* Integer: zero- or sign-extended in r2. */ + if (out != NULL) + regcache_cooked_read_part (regcache, S390_R2_REGNUM, + word_size - length, length, out); + else if (TYPE_UNSIGNED (type)) + regcache_cooked_write_unsigned + (regcache, S390_R2_REGNUM, + extract_unsigned_integer (in, length, byte_order)); + else + regcache_cooked_write_signed + (regcache, S390_R2_REGNUM, + extract_signed_integer (in, length, byte_order)); } + else if (length == 2 * word_size) + { + /* Double word: in r2 and r3. */ + if (in != NULL) + { + regcache_cooked_write (regcache, S390_R2_REGNUM, in); + regcache_cooked_write (regcache, S390_R3_REGNUM, + in + word_size); + } + else + { + regcache_cooked_read (regcache, S390_R2_REGNUM, out); + regcache_cooked_read (regcache, S390_R3_REGNUM, + out + word_size); + } + } + else + internal_error (__FILE__, __LINE__, _("invalid return type")); } + +/* Implement the 'return_value' gdbarch method. */ + static enum return_value_convention s390_return_value (struct gdbarch *gdbarch, struct value *function, struct type *type, struct regcache *regcache, gdb_byte *out, const gdb_byte *in) { - enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); - int word_size = gdbarch_ptr_bit (gdbarch) / 8; enum return_value_convention rvc; - int length; type = check_typedef (type); - rvc = s390_return_value_convention (gdbarch, type); - length = TYPE_LENGTH (type); - if (in) + switch (TYPE_CODE (type)) { - switch (rvc) - { - case RETURN_VALUE_REGISTER_CONVENTION: - if (TYPE_CODE (type) == TYPE_CODE_FLT - || TYPE_CODE (type) == TYPE_CODE_DECFLOAT) - { - /* When we store a single-precision value in an FP register, - it occupies the leftmost bits. */ - regcache_cooked_write_part (regcache, S390_F0_REGNUM, - 0, length, in); - } - else if (length <= word_size) - { - /* Integer arguments are always extended to word size. */ - if (TYPE_UNSIGNED (type)) - regcache_cooked_write_unsigned (regcache, S390_R2_REGNUM, - extract_unsigned_integer (in, length, byte_order)); - else - regcache_cooked_write_signed (regcache, S390_R2_REGNUM, - extract_signed_integer (in, length, byte_order)); - } - else if (length == 2*word_size) - { - regcache_cooked_write (regcache, S390_R2_REGNUM, in); - regcache_cooked_write (regcache, S390_R3_REGNUM, in + word_size); - } - else - internal_error (__FILE__, __LINE__, _("invalid return type")); - break; - - case RETURN_VALUE_STRUCT_CONVENTION: - error (_("Cannot set function return value.")); - break; - } + case TYPE_CODE_STRUCT: + case TYPE_CODE_UNION: + case TYPE_CODE_ARRAY: + case TYPE_CODE_COMPLEX: + rvc = RETURN_VALUE_STRUCT_CONVENTION; + break; + default: + rvc = TYPE_LENGTH (type) <= 8 + ? RETURN_VALUE_REGISTER_CONVENTION + : RETURN_VALUE_STRUCT_CONVENTION; } - else if (out) + + if (in != NULL || out != NULL) { - switch (rvc) - { - case RETURN_VALUE_REGISTER_CONVENTION: - if (TYPE_CODE (type) == TYPE_CODE_FLT - || TYPE_CODE (type) == TYPE_CODE_DECFLOAT) - { - /* When we store a single-precision value in an FP register, - it occupies the leftmost bits. */ - regcache_cooked_read_part (regcache, S390_F0_REGNUM, - 0, length, out); - } - else if (length <= word_size) - { - /* Integer arguments occupy the rightmost bits. */ - regcache_cooked_read_part (regcache, S390_R2_REGNUM, - word_size - length, length, out); - } - else if (length == 2*word_size) - { - regcache_cooked_read (regcache, S390_R2_REGNUM, out); - regcache_cooked_read (regcache, S390_R3_REGNUM, out + word_size); - } - else - internal_error (__FILE__, __LINE__, _("invalid return type")); - break; - - case RETURN_VALUE_STRUCT_CONVENTION: - error (_("Function return value unknown.")); - break; - } + if (rvc == RETURN_VALUE_REGISTER_CONVENTION) + s390_register_return_value (gdbarch, type, regcache, out, in); + else if (in != NULL) + error (_("Cannot set function return value.")); + else + error (_("Function return value unknown.")); } return rvc;