[llvm-commits] [llvm] r70768 - /llvm/trunk/lib/Target/MSP430/README.txt

[Anton Korobeynikov]

Hi, Dan

> I'm not familiar with MSP430, but this sounds very similar to x86-64's
> implicit
> zext with 32-bit operands.   An i64-to-i32 truncate is selected to an
> EXTRACT_SUBREG, and an i64-to-i32 zext is selected to a
> SUBREG_TO_REG when the operand isn't a truncate.  There's a regular
> i32-to-i64 zext instruction which is used when the operand is a
> truncate.
Ah, right. I completely forgot about this :) I'm modelling truncate
via extract_subreg, but not implicit zext. Will think about this
solution.

PS: I'm also not familiar with MSP430 as stated in the disclaimer.
It's just small and pretty clean MCU which can be used to demonstrate
backend writing.
-- 
With best regards, Anton Korobeynikov
Faculty of Mathematics and Mechanics, Saint Petersburg State University