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Re: Help restricting args of an intrinsic function
On Jan 30, 2004, at 5:42 PM, David Edelsohn wrote:
Ian Lance Taylor writes:
How do I collapse it down to a const_int?
Ian> You use a constraint of 'n'.
The PowerPC port already provides special 'h' and 'H' constraints
for the 32-bit version and 64-bit instructions.
According to the internals manual:
An immediate integer operand with a known numeric value is allowed.
Many systems cannot support assembly-time constants for operands less
than a word wide. Constraints for these operands should use n rather
MQ, CTR, or LINK register
I am a complete beginner to gcc, so forgive my naive questions. But
what is the difference between these two? h looks like it is a 32 bit
value. n looks like a general assembly-constant less than one word
wide. Since the assembly constants I need are 5 bits wide, it looks
like n is the correct one to use.
Why would I use h?
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