[LLVMdev] ARM Intruction Constraint DestReg!=SrcReg patch?

Gergö Barany gergo at complang.tuwien.ac.at
Fri Nov 26 01:01:26 PST 2010

On Fri, Nov 26, 2010 at 08:59:54 +0100, maarten faddegon wrote:
> Thus, if I want to follow this advice, is there a way to force LLVM to 
> not output instructions such as "mul r0, r0, r2"?

If you're fine with using the PBQP register allocator, it would be very
simple to extend the PBQP formulation with a constraint that prohibits
allocating the result and one of the source operands to the same register.

Gergö Barany, research assistant                   gergo at complang.tuwien.ac.at
Institute of Computer Languages        http://www.complang.tuwien.ac.at/gergo/
Vienna University of Technology                         Tel: +43-1-58801-58522
Argentinierstrasse 8/E185, 1040 Wien, Austria           Fax: +43-1-58801-18598

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