Has Fast register allocation been finished in 3.3 version?

When I use llc command with --regalloc=fast , get error

In addition, is lli use fast register allocation?

You should probably ask about this on the llvmdev mailing list, you’ll reach the right audience there.

-Chris

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发件人:“Chris Lattner” <clattner@apple.com>
日期:2013年10月22日 下午7:33
主题:Re: [lldb-dev] Has Fast register allocation been finished in 3.3 version?
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---------- 转发的邮件 ----------
发件人:“Chris Lattner” <clattner@apple.com>
日期:2013年10月22日 下午7:33
主题:Re: [lldb-dev] Has Fast register allocation been finished in 3.3 version?
收件人: <wansheg@gmail.com>
抄送: <lldb-dev@cs.uiuc.edu>

When I use llc command with --regalloc=fast , get error

And I presume the error is:
LLVM ERROR: regalloc=… not currently supported with -O0

-regalloc=fast is not a very useful flag because it requires “-O0” and is also implied by -O0.

However, if you still want all the other llc optimizations you can use an internal option instead of -O0:

-optimize-regalloc=false -regalloc=fast

Register allocation is not just the allocation algorithm. It’s a set of passes that cooperate. The ‘fast’ allocator uses a different pipeline than the optimizing global allocators.

In addition, is lli use fast register allocation?

AFAIK, the -O levels are the same, with -O0 using fast regalloc.

-Andy