[LLVMbugs] [Bug 21127] New: Clang does not support ARMv6k

[bugzilla-daemon at llvm.org]

http://llvm.org/bugs/show_bug.cgi?id=21127

            Bug ID: 21127
           Summary: Clang does not support ARMv6k
           Product: clang
           Version: trunk
          Hardware: All
                OS: All
            Status: NEW
          Severity: enhancement
          Priority: P
         Component: Driver
          Assignee: unassignedclangbugs at nondot.org
          Reporter: t.p.northover at gmail.com
                CC: llvmbugs at cs.uiuc.edu
    Classification: Unclassified

E.g.

$ cat tmp.c
void foo() {
  asm volatile("wfe");
}
$ clang -target arm-linux-gnueabi -march=armv6k tmp.c -c
<inline asm>:1:2: error: instruction requires: armv6t2
        wfe

There are 2 problems here:

1. Clang treats "armv6k" the same as "armv6" for -march purposes (and defaults
to arm1136jf-s). It's actually a slight enhancement over stock v6, including
the WFE instruction in ARM mode. It should probably default to arm1176jzf-s,
since that's the first (and only) CPU guaranteed to have v6k but not others.

2. LLVM doesn't know about armv6k either. ARM1176JZF-S is treated as a plain
armv6 CPU by the backend and won't allow WFE to be assembled.

-- 
You are receiving this mail because:
You are on the CC list for the bug.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.llvm.org/pipermail/llvm-bugs/attachments/20141001/2196a787/attachment.html>