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Change memcpy/memove/memset to have dest and source alignment attributes (Step…

Description

Change memcpy/memove/memset to have dest and source alignment attributes (Step 1).

Summary:

Upstream LLVM is changing the the prototypes of the @llvm.memcpy/memmove/memset

intrinsics. This change updates the Clang tests for this change.

The @llvm.memcpy/memmove/memset intrinsics currently have an explicit argument

which is required to be a constant integer. It represents the alignment of the
dest (and source), and so must be the minimum of the actual alignment of the
two.

This change removes the alignment argument in favour of placing the alignment
attribute on the source and destination pointers of the memory intrinsic call.

For example, code which used to read:

call void @llvm.memcpy.p0i8.p0i8.i32(i8* %dest, i8* %src, i32 100, i32 4, i1 false)

will now read

call void @llvm.memcpy.p0i8.p0i8.i32(i8* align 4 %dest, i8* align 4 %src, i32 100, i1 false)

At this time the source and destination alignments must be the same (Step 1).
Step 2 of the change, to be landed shortly, will relax that contraint and allow
the source and destination to have different alignments.

Details

Committed
dneilsonJan 19 2018, 9:12 AM
Parents
rL322963: Change memcpy/memove/memset to have dest and source alignment attributes (Step…
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