Change memcpy/memset/memmove to have dest and source alignments.

Note, this was reviewed (and more details are in) http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20151109/312083.html

These intrinsics currently have an explicit alignment argument which is
required to be a constant integer.  It represents the alignment of the
source and dest, and so must be the minimum of those.

This change allows source and dest to each have their own alignments
by using the alignment attribute on their arguments.  The alignment
argument itself is removed.

There are a few places in the code for which the code needs to be
checked by an expert as to whether using only src/dest alignment is
safe.  For those places, they currently take the minimum of src/dest
alignments which matches the current behaviour.

For example, code which used to read:
  call void @llvm.memcpy.p0i8.p0i8.i32(i8* %dest, i8* %src, i32 500, i32 8, i1 false)
will now read:
  call void @llvm.memcpy.p0i8.p0i8.i32(i8* align 8 %dest, i8* align 8 %src, i32 500, i1 false)

For out of tree owners, I was able to strip alignment from calls using sed by replacing:
  (call.*llvm\.memset.*)i32\ [0-9]*\,\ i1 false\)
with:
  $1i1 false)

and similarly for memmove and memcpy.

I then added back in alignment to test cases which needed it.

A similar commit will be made to clang which actually has many differences in alignment as now
IRBuilder can generate different source/dest alignments on calls.

In IRBuilder itself, a new argument was added.  Instead of calling:
  CreateMemCpy(Dst, Src, getInt64(Size), DstAlign, /* isVolatile */ false)
you now call
  CreateMemCpy(Dst, Src, getInt64(Size), DstAlign, SrcAlign, /* isVolatile */ false)

There is a temporary class (IntegerAlignment) which takes the source alignment and rejects
implicit conversion from bool.  This is to prevent isVolatile here from passing its default
parameter to the source alignment.

Note, changes in future can now be made to codegen.  I didn't change anything here, but this
change should enable better memcpy code sequences.

Reviewed by Hal Finkel.

llvm-svn: 253511

1 files changed, 14 insertions, 14 deletions

diff --git a/llvm/test/CodeGen/PowerPC/resolvefi-basereg.ll b/llvm/test/CodeGen/PowerPC/resolvefi-basereg.ll
index a613c3310a5..c3e63d5342f 100644
--- a/llvm/test/CodeGen/PowerPC/resolvefi-basereg.ll
+++ b/llvm/test/CodeGen/PowerPC/resolvefi-basereg.ll
@@ -32,9 +32,9 @@ entry:
   %agg.tmp117 = alloca %struct.S1998, align 16
   %agg.tmp118 = alloca %struct.S1998, align 16
   %agg.tmp119 = alloca %struct.S1998, align 16
-  call void @llvm.memset.p0i8.i64(i8* bitcast (%struct.S1998* @s1998 to i8*), i8 0, i64 5168, i32 16, i1 false)
-  call void @llvm.memset.p0i8.i64(i8* bitcast ([5 x %struct.S1998]* @a1998 to i8*), i8 0, i64 25840, i32 16, i1 false)
-  call void @llvm.memset.p0i8.i64(i8* bitcast (%struct.Info* @info to i8*), i8 0, i64 832, i32 8, i1 false)
+  call void @llvm.memset.p0i8.i64(i8* bitcast (%struct.S1998* @s1998 to i8*), i8 0, i64 5168, i1 false)
+  call void @llvm.memset.p0i8.i64(i8* bitcast ([5 x %struct.S1998]* @a1998 to i8*), i8 0, i64 25840, i1 false)
+  call void @llvm.memset.p0i8.i64(i8* bitcast (%struct.Info* @info to i8*), i8 0, i64 832, i1 false)
   store i8* bitcast (%struct.S1998* @s1998 to i8*), i8** getelementptr inbounds (%struct.Info, %struct.Info* @info, i32 0, i32 2), align 8
   store i8* bitcast ([5 x %struct.S1998]* @a1998 to i8*), i8** getelementptr inbounds (%struct.Info, %struct.Info* @info, i32 0, i32 3), align 8
   store i8* bitcast (%struct.S1998* getelementptr inbounds ([5 x %struct.S1998], [5 x %struct.S1998]* @a1998, i32 0, i64 3) to i8*), i8** getelementptr inbounds (%struct.Info, %struct.Info* @info, i32 0, i32 4), align 8
@@ -329,32 +329,32 @@ if.end:                                           ; preds = %if.then, %entry
   %61 = load i32, i32* %j, align 4
   store i32 %61, i32* getelementptr inbounds (%struct.Info, %struct.Info* @info, i32 0, i32 1), align 4
   %62 = bitcast %struct.S1998* %agg.tmp111 to i8*
-  call void @llvm.memcpy.p0i8.p0i8.i64(i8* %62, i8* bitcast (%struct.S1998* @s1998 to i8*), i64 5168, i32 16, i1 false)
+  call void @llvm.memcpy.p0i8.p0i8.i64(i8* %62, i8* bitcast (%struct.S1998* @s1998 to i8*), i64 5168, i1 false)
   %63 = bitcast %struct.S1998* %agg.tmp112 to i8*
-  call void @llvm.memcpy.p0i8.p0i8.i64(i8* %63, i8* bitcast (%struct.S1998* getelementptr inbounds ([5 x %struct.S1998], [5 x %struct.S1998]* @a1998, i32 0, i64 2) to i8*), i64 5168, i32 16, i1 false)
+  call void @llvm.memcpy.p0i8.p0i8.i64(i8* %63, i8* bitcast (%struct.S1998* getelementptr inbounds ([5 x %struct.S1998], [5 x %struct.S1998]* @a1998, i32 0, i64 2) to i8*), i64 5168, i1 false)
   call void @check1998(%struct.S1998* sret %agg.tmp, %struct.S1998* byval align 16 %agg.tmp111, %struct.S1998* getelementptr inbounds ([5 x %struct.S1998], [5 x %struct.S1998]* @a1998, i32 0, i64 1), %struct.S1998* byval align 16 %agg.tmp112)
   call void @checkx1998(%struct.S1998* byval align 16 %agg.tmp)
   %64 = bitcast %struct.S1998* %agg.tmp113 to i8*
-  call void @llvm.memcpy.p0i8.p0i8.i64(i8* %64, i8* bitcast (%struct.S1998* @s1998 to i8*), i64 5168, i32 16, i1 false)
+  call void @llvm.memcpy.p0i8.p0i8.i64(i8* %64, i8* bitcast (%struct.S1998* @s1998 to i8*), i64 5168, i1 false)
   %65 = bitcast %struct.S1998* %agg.tmp114 to i8*
-  call void @llvm.memcpy.p0i8.p0i8.i64(i8* %65, i8* bitcast (%struct.S1998* getelementptr inbounds ([5 x %struct.S1998], [5 x %struct.S1998]* @a1998, i32 0, i64 2) to i8*), i64 5168, i32 16, i1 false)
+  call void @llvm.memcpy.p0i8.p0i8.i64(i8* %65, i8* bitcast (%struct.S1998* getelementptr inbounds ([5 x %struct.S1998], [5 x %struct.S1998]* @a1998, i32 0, i64 2) to i8*), i64 5168, i1 false)
   %66 = bitcast %struct.S1998* %agg.tmp115 to i8*
-  call void @llvm.memcpy.p0i8.p0i8.i64(i8* %66, i8* bitcast (%struct.S1998* getelementptr inbounds ([5 x %struct.S1998], [5 x %struct.S1998]* @a1998, i32 0, i64 2) to i8*), i64 5168, i32 16, i1 false)
+  call void @llvm.memcpy.p0i8.p0i8.i64(i8* %66, i8* bitcast (%struct.S1998* getelementptr inbounds ([5 x %struct.S1998], [5 x %struct.S1998]* @a1998, i32 0, i64 2) to i8*), i64 5168, i1 false)
   call void (i32, ...) @check1998va(i32 signext 1, double 1.000000e+00, %struct.S1998* byval align 16 %agg.tmp113, i64 2, %struct.S1998* byval align 16 %agg.tmp114, %struct.S1998* byval align 16 %agg.tmp115)
   %67 = bitcast %struct.S1998* %agg.tmp116 to i8*
-  call void @llvm.memcpy.p0i8.p0i8.i64(i8* %67, i8* bitcast (%struct.S1998* @s1998 to i8*), i64 5168, i32 16, i1 false)
+  call void @llvm.memcpy.p0i8.p0i8.i64(i8* %67, i8* bitcast (%struct.S1998* @s1998 to i8*), i64 5168, i1 false)
   %68 = bitcast %struct.S1998* %agg.tmp117 to i8*
-  call void @llvm.memcpy.p0i8.p0i8.i64(i8* %68, i8* bitcast (%struct.S1998* @s1998 to i8*), i64 5168, i32 16, i1 false)
+  call void @llvm.memcpy.p0i8.p0i8.i64(i8* %68, i8* bitcast (%struct.S1998* @s1998 to i8*), i64 5168, i1 false)
   %69 = bitcast %struct.S1998* %agg.tmp118 to i8*
-  call void @llvm.memcpy.p0i8.p0i8.i64(i8* %69, i8* bitcast (%struct.S1998* getelementptr inbounds ([5 x %struct.S1998], [5 x %struct.S1998]* @a1998, i32 0, i64 2) to i8*), i64 5168, i32 16, i1 false)
+  call void @llvm.memcpy.p0i8.p0i8.i64(i8* %69, i8* bitcast (%struct.S1998* getelementptr inbounds ([5 x %struct.S1998], [5 x %struct.S1998]* @a1998, i32 0, i64 2) to i8*), i64 5168, i1 false)
   %70 = bitcast %struct.S1998* %agg.tmp119 to i8*
-  call void @llvm.memcpy.p0i8.p0i8.i64(i8* %70, i8* bitcast (%struct.S1998* @s1998 to i8*), i64 5168, i32 16, i1 false)
+  call void @llvm.memcpy.p0i8.p0i8.i64(i8* %70, i8* bitcast (%struct.S1998* @s1998 to i8*), i64 5168, i1 false)
   call void (i32, ...) @check1998va(i32 signext 2, %struct.S1998* byval align 16 %agg.tmp116, %struct.S1998* byval align 16 %agg.tmp117, ppc_fp128 0xM40000000000000000000000000000000, %struct.S1998* byval align 16 %agg.tmp118, %struct.S1998* byval align 16 %agg.tmp119)
   ret void
 }
 
-declare void @llvm.memset.p0i8.i64(i8* nocapture, i8, i64, i32, i1)
-declare void @llvm.memcpy.p0i8.p0i8.i64(i8* nocapture, i8* nocapture readonly, i64, i32, i1)
+declare void @llvm.memset.p0i8.i64(i8* nocapture, i8, i64, i1)
+declare void @llvm.memcpy.p0i8.p0i8.i64(i8* nocapture, i8* nocapture readonly, i64, i1)
 
 declare void @check1998(%struct.S1998* sret, %struct.S1998* byval align 16, %struct.S1998*, %struct.S1998* byval align 16)
 declare void @check1998va(i32 signext, ...)