Bug 20703 - [gas][x86] Cannot assemble certain registers for vpmuludq instruction
Summary: [gas][x86] Cannot assemble certain registers for vpmuludq instruction
Status: RESOLVED WORKSFORME
Alias: None
Product: binutils
Classification: Unclassified
Component: gas (show other bugs)
Version: 2.26
: P2 normal
Target Milestone: ---
Assignee: Not yet assigned to anyone
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 2016-10-17 17:33 UTC by nholcomb
Modified: 2017-03-09 17:15 UTC (History)
1 user (show)

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Last reconfirmed: 2016-10-17 00:00:00

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Description nholcomb 2016-10-17 17:33:34 UTC 
The following instruction produced by objdump cannot be assembled by GAS due to an error:

Bytes: 62 c1 95 00 f4 41 42
Instruction: vpmuludq 0x420(%r9), %xmm29, %xmm16
ERROR:  invalid register operand for `vpmuludq'

This might be a limitation on the part of gas. Checking other decoders like XED and LLVM, the instruction appears to be valid.
Comment 1 H.J. Lu 2016-10-17 22:53:52 UTC 
[hjl@gnu-6 mbind]$ cat x.s
vpmuludq 0x420(%r9),%xmm29,%xmm16
[hjl@gnu-6 mbind]$ gcc -c x.s
[hjl@gnu-6 mbind]$ objdump -dwr x.o

x.o:     file format elf64-x86-64


Disassembly of section .text:

0000000000000000 <.text>:
   0:	62 c1 95 00 f4 41 42 	vpmuludq 0x420(%r9),%xmm29,%xmm16
[hjl@gnu-6 mbind]$
Comment 2 H.J. Lu 2017-03-09 17:15:49 UTC 
Works with binutils 2.28.