diff options
| author | H.J. Lu <hjl.tools@gmail.com> | 2019-05-02 10:46:55 -0700 |
|---|---|---|
| committer | H.J. Lu <hjl.tools@gmail.com> | 2019-05-02 10:47:04 -0700 |
| commit | 06f74c5cb868cfd37af3e680d29784c217700bdf (patch) | |
| tree | cb19afcc9839414386df4b0e684604ea6d2a17ae /gas/config | |
| parent | b8c05e85ef4ce9610a3a43198180cf24aea327cb (diff) | |
| download | gdb-06f74c5cb868cfd37af3e680d29784c217700bdf.zip gdb-06f74c5cb868cfd37af3e680d29784c217700bdf.tar.gz gdb-06f74c5cb868cfd37af3e680d29784c217700bdf.tar.bz2 | |
i386: Issue a warning to IRET without suffix for .code16gcc
The .code16gcc directive to support 16-bit mode with 32-bit address.
For IRET without a suffix, generate 16-bit IRET with a warning to
return from an interrupt handler in 16-bit mode.
PR gas/24485
* config/tc-i386.c (process_suffix): Issue a warning to IRET
without a suffix for .code16gcc.
* testsuite/gas/i386/jump16.s: Add tests for iretX.
* testsuite/gas/i386/jump16.d: Updated.
* testsuite/gas/i386/jump16.e: New file.
Diffstat (limited to 'gas/config')
| -rw-r--r-- | gas/config/tc-i386.c | 20 |
1 files changed, 13 insertions, 7 deletions
diff --git a/gas/config/tc-i386.c b/gas/config/tc-i386.c index 032b1d3..7159432 100644 --- a/gas/config/tc-i386.c +++ b/gas/config/tc-i386.c @@ -6242,7 +6242,19 @@ process_suffix (void) /* exclude fldenv/frstor/fsave/fstenv */ && i.tm.opcode_modifier.no_ssuf) { - i.suffix = stackop_size; + if (stackop_size == LONG_MNEM_SUFFIX + && i.tm.base_opcode == 0xcf) + { + /* stackop_size is set to LONG_MNEM_SUFFIX for the + .code16gcc directive to support 16-bit mode with + 32-bit address. For IRET without a suffix, generate + 16-bit IRET (opcode 0xcf) to return from an interrupt + handler. */ + i.suffix = WORD_MNEM_SUFFIX; + as_warn (_("generating 16-bit `iret' for .code16gcc directive")); + } + else + i.suffix = stackop_size; } else if (intel_syntax && !i.suffix @@ -6352,13 +6364,7 @@ process_suffix (void) if (!add_prefix (ADDR_PREFIX_OPCODE)) return 0; } - /* stackop_size is set to LONG_MNEM_SUFFIX for the .code16gcc - directive to support 16bit mode with 32-bit address. Since - IRET (opcode 0xcf) in 16bit mode returns from an interrupt - in 16bit mode, we shouldn't add DATA_PREFIX_OPCODE here. */ else if (i.suffix != QWORD_MNEM_SUFFIX - && (stackop_size != LONG_MNEM_SUFFIX - || i.tm.base_opcode != 0xcf) && !i.tm.opcode_modifier.ignoresize && !i.tm.opcode_modifier.floatmf && !i.tm.opcode_modifier.vex |