align.ll 1.4 KB

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  1. ; RUN: opt < %s -S -basicaa -memcpyopt | FileCheck %s
  2. target datalayout = "E-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64"
  3. declare void @llvm.memcpy.p0i8.p0i8.i64(i8* nocapture, i8* nocapture, i64, i32, i1) nounwind
  4. declare void @llvm.memset.p0i8.i64(i8* nocapture, i8, i64, i32, i1) nounwind
  5. ; The resulting memset is only 4-byte aligned, despite containing
  6. ; a 16-byte aligned store in the middle.
  7. define void @foo(i32* %p) {
  8. ; CHECK-LABEL: @foo(
  9. ; CHECK: call void @llvm.memset.p0i8.i64(i8* {{.*}}, i8 0, i64 16, i32 4, i1 false)
  10. %a0 = getelementptr i32, i32* %p, i64 0
  11. store i32 0, i32* %a0, align 4
  12. %a1 = getelementptr i32, i32* %p, i64 1
  13. store i32 0, i32* %a1, align 16
  14. %a2 = getelementptr i32, i32* %p, i64 2
  15. store i32 0, i32* %a2, align 4
  16. %a3 = getelementptr i32, i32* %p, i64 3
  17. store i32 0, i32* %a3, align 4
  18. ret void
  19. }
  20. ; Replacing %a8 with %a4 in the memset requires boosting the alignment of %a4.
  21. define void @bar() {
  22. ; CHECK-LABEL: @bar(
  23. ; CHECK: %a4 = alloca i32, align 8
  24. ; CHECK-NOT: memcpy
  25. %a4 = alloca i32, align 4
  26. %a8 = alloca i32, align 8
  27. %a8.cast = bitcast i32* %a8 to i8*
  28. %a4.cast = bitcast i32* %a4 to i8*
  29. call void @llvm.memset.p0i8.i64(i8* %a8.cast, i8 0, i64 4, i32 8, i1 false)
  30. call void @llvm.memcpy.p0i8.p0i8.i64(i8* %a4.cast, i8* %a8.cast, i64 4, i32 4, i1 false)
  31. ret void
  32. }