Zachary Turner dc88b88a05 [Support] Add some helpers to generate bitmasks. ... Frequently you you want a bitmask consisting of a specified number of 1s, either at the beginning or end of a word. The naive way to do this is to write template<typename T> T leadingBitMask(unsigned N) { return (T(1) << N) - 1; } but using this function you cannot produce a word with every bit set to 1 (i.e. leadingBitMask<uint8_t>(8)) because left shift is undefined when N is greater than or equal to the number of bits in the word. This patch provides an efficient, branch-free implementation that works for all values of N in [0, CHAR_BIT*sizeof(T)] Differential Revision: https://reviews.llvm.org/D32212 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@300710 91177308-0d34-0410-b5e6-96231b3b80d8		2017-04-19 15:45:31 +00:00
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llvm	[Support] Add some helpers to generate bitmasks.	2017-04-19 15:45:31 +00:00
llvm-c	Introducing LLVMMetadataRef	2017-04-17 11:52:54 +00:00