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| author | H.J. Lu <hjl.tools@gmail.com> | 2018-09-13 06:12:31 -0700 |
|---|---|---|
| committer | H.J. Lu <hjl.tools@gmail.com> | 2018-09-13 06:12:31 -0700 |
| commit | 79f0fa25b95fd82122ee76d61fded661cc3ece87 (patch) | |
| tree | 6a00f3583a867b6f5e4a60ed2268801e03e8ead7 /gas | |
| parent | 57f6375ec10415fc26bbfaf4fdc19effb313a06d (diff) | |
| download | gdb-79f0fa25b95fd82122ee76d61fded661cc3ece87.zip gdb-79f0fa25b95fd82122ee76d61fded661cc3ece87.tar.gz gdb-79f0fa25b95fd82122ee76d61fded661cc3ece87.tar.bz2 | |
x86: Swap destination/source to encode VEX only if possible
When encoding VEX, we can swap destination and source only if there are
more than 1 register operand.
* config/tc-i386.c (build_vex_prefix): Swap destination and
source only if there are more than 1 register operand.
Diffstat (limited to 'gas')
| -rw-r--r-- | gas/ChangeLog | 5 | ||||
| -rw-r--r-- | gas/config/tc-i386.c | 7 |
2 files changed, 9 insertions, 3 deletions
diff --git a/gas/ChangeLog b/gas/ChangeLog index 7a82555..fc17226 100644 --- a/gas/ChangeLog +++ b/gas/ChangeLog @@ -1,3 +1,8 @@ +2018-09-13 H.J. Lu <hongjiu.lu@intel.com> + + * config/tc-i386.c (build_vex_prefix): Swap destination and + source only if there are more than 1 register operand. + 2018-09-13 Jan Beulich <jbeulich@suse.com> * config/tc-i386.c (operand_size_match): Also deal with three diff --git a/gas/config/tc-i386.c b/gas/config/tc-i386.c index 2bff48a..40b4583 100644 --- a/gas/config/tc-i386.c +++ b/gas/config/tc-i386.c @@ -3364,9 +3364,10 @@ build_vex_prefix (const insn_template *t) else register_specifier = 0xf; - /* Use 2-byte VEX prefix by swapping destination and source - operand. */ - if (i.vec_encoding != vex_encoding_vex3 + /* Use 2-byte VEX prefix by swapping destination and source operand + if there are more than 1 register operand. */ + if (i.reg_operands > 1 + && i.vec_encoding != vex_encoding_vex3 && i.dir_encoding == dir_encoding_default && i.operands == i.reg_operands && operand_type_equal (&i.types[0], &i.types[i.operands - 1]) |