[LLVMdev] thumb2 folding of constant addresses unhelpful

Evan Cheng evan.cheng at apple.com
Tue Dec 1 14:57:06 PST 2009

Right. I am aware of this problem but am not sure about what to do about it. It's common for a number 32-bit immediates in the same block with the same lower or higher 16-bit. Since the immediates will not be split until late in codegen, the target independent optimizer will not CSE them.

Please file a bug, I need to think about a proper solution.


On Dec 1, 2009, at 11:19 AM, Bagel wrote:

> When addresses are a displacement from a constant (this can happen in device drivers), the resulting address gets folded rather than using base+displacement addressing.  This results in code bloat.  Example test attached.
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