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A comment on A Quiz About Integers in C. Parent comment

Re:A Quiz About Integers in C by nitrogen on Monday June 04, 2012 @12:16PM (#4064627)
Does that imply that PPC is limited to shifting at most 15 bits at a time?
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Re:A Quiz About Integers in C by astrange on Tuesday June 05, 2012 @12:05AM (#4067272)
In fact the answer was 5 bits for 32bit and 7 bits for 64bit[1]. x86-64 uses 5 bits for 32bit and for 64bit (shld/shrd can't shift more than 31 bits).

7 bits is problematic because some code may assume that x << -y is an optimization for x << (32-y). I thought there was some architecture where this assumption didn't work on 32bit either, which led to my post above.

[1] http://pic.dhe.ibm.com/infocenter/aix/v7r1/topic/com.ibm.aix...

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