diff options
Diffstat (limited to 'packages/gdb/10.2/0015-gdb-Fix-numerical-field-extraction-for-target-descri.patch')
| -rw-r--r-- | packages/gdb/10.2/0015-gdb-Fix-numerical-field-extraction-for-target-descri.patch | 101 |
1 files changed, 101 insertions, 0 deletions
diff --git a/packages/gdb/10.2/0015-gdb-Fix-numerical-field-extraction-for-target-descri.patch b/packages/gdb/10.2/0015-gdb-Fix-numerical-field-extraction-for-target-descri.patch new file mode 100644 index 00000000..ba510bdc --- /dev/null +++ b/packages/gdb/10.2/0015-gdb-Fix-numerical-field-extraction-for-target-descri.patch @@ -0,0 +1,101 @@ +From b99b999fc7a0d0888b62e3bdedd0b4855bdf955c Mon Sep 17 00:00:00 2001 +From: Shahab Vahedi <shahab@synopsys.com> +Date: Fri, 16 Jul 2021 16:49:15 +0200 +Subject: [PATCH 18/20] gdb: Fix numerical field extraction for target + description "flags" + +The "val_print_type_code_flags ()" function is responsible for +extraction of fields for "flags" data type. These data types are +used when describing a custom register type in a target description +XML. The logic used for the extraction though is not sound: + + unsigned field_len = TYPE_FIELD_BITSIZE (type, field); + ULONGEST field_val + = val >> (TYPE_FIELD_BITPOS (type, field) - field_len + 1); + +TYPE_FIELD_BITSIZE: The bit length of the field to be extracted. +TYPE_FIELD_BITPOS: The starting position of the field; 0 is LSB. +val: The register value. + +Imagine you have a field that starts at position 1 and its length +is 4 bits. According to the third line of the code snippet the +shifting right would become "val >> -2", or "val >> 0xfff...fe" +to be precise. That will result in a "field_val" of 0. + +The correct extraction should be: + + ULONGEST field_val = val >> TYPE_FIELD_BITPOS (type, field); + +The rest of the algorithm that masks out the higher bits is OK. + +Co-Authored-By: Simon Marchi <simon.marchi@efficios.com> + +Will be a part of GDB 11: +https://sourceware.org/git?p=binutils-gdb.git;a=commit;h=c9bd98593b785d9bf5f39c7aa74ed0226a23b830 +--- + gdb/valprint.c | 36 ++++++++++++++++++++++++++++++++++-- + 1 file changed, 34 insertions(+), 2 deletions(-) + +--- a/gdb/valprint.c ++++ b/gdb/valprint.c +@@ -40,6 +40,8 @@ + #include "gdbarch.h" + #include "cli/cli-style.h" + #include "count-one-bits.h" ++#include "gdbsupport/selftest.h" ++#include "selftest-arch.h" + + /* Maximum number of wchars returned from wchar_iterate. */ + #define MAX_WCHARS 4 +@@ -1157,8 +1159,7 @@ + else + { + unsigned field_len = TYPE_FIELD_BITSIZE (type, field); +- ULONGEST field_val +- = val >> (TYPE_FIELD_BITPOS (type, field) - field_len + 1); ++ ULONGEST field_val = val >> TYPE_FIELD_BITPOS (type, field); + + if (field_len < sizeof (ULONGEST) * TARGET_CHAR_BIT) + field_val &= ((ULONGEST) 1 << field_len) - 1; +@@ -3100,10 +3101,41 @@ + return {{value_print_option_defs}, opts}; + } + ++#if GDB_SELF_TEST ++ ++/* Test printing of TYPE_CODE_FLAGS values. */ ++ ++static void ++test_print_flags (gdbarch *arch) ++{ ++ type *flags_type = arch_flags_type (arch, "test_type", 32); ++ type *field_type = builtin_type (arch)->builtin_uint32; ++ ++ /* Value: 1010 1010 ++ Fields: CCCB BAAA */ ++ append_flags_type_field (flags_type, 0, 3, field_type, "A"); ++ append_flags_type_field (flags_type, 3, 2, field_type, "B"); ++ append_flags_type_field (flags_type, 5, 3, field_type, "C"); ++ ++ value *val = allocate_value (flags_type); ++ gdb_byte *contents = value_contents_writeable (val); ++ store_unsigned_integer (contents, 4, gdbarch_byte_order (arch), 0xaa); ++ ++ string_file out; ++ val_print_type_code_flags (flags_type, val, 0, &out); ++ SELF_CHECK (out.string () == "[ A=2 B=1 C=5 ]"); ++} ++ ++#endif ++ + void _initialize_valprint (); + void + _initialize_valprint () + { ++#if GDB_SELF_TEST ++ selftests::register_test_foreach_arch ("print-flags", test_print_flags); ++#endif ++ + cmd_list_element *cmd; + + add_basic_prefix_cmd ("print", no_class, |