[AArch64] Support SLC in ACLE prefetch intrinsics

This change:
- Modifies the ACLE code to allow the new SLC value (3) for the prefetch
  target.

- Introduces a new intrinsic, @llvm.aarch64.prefetch which matches the
  PRFM family instructions much more closely, and can represent all
  values for the PRFM immediate.

  The target-independent @llvm.prefetch intrinsic does not have enough
  information for us to be able to lower to it from the ACLE intrinsics
  correctly.

- Lowers the acle calls to the new intrinsic on aarch64 (the ARM
  lowering is unchanged).

- Implements code generation for the new intrinsic in both SelectionDAG
  and GlobalISel. We specifically choose to continue to support lowering
  the target-independent @llvm.prefetch intrinsic so that other
  frontends can continue to use it.

Differential Revision: https://reviews.llvm.org/D139443

1 files changed, 3 insertions, 3 deletions

diff --git a/clang/lib/Sema/SemaChecking.cpp b/clang/lib/Sema/SemaChecking.cpp
index 9f0c849..86f1c3c 100644
--- a/clang/lib/Sema/SemaChecking.cpp
+++ b/clang/lib/Sema/SemaChecking.cpp
@@ -3226,9 +3226,9 @@ bool Sema::CheckAArch64BuiltinFunctionCall(const TargetInfo &TI,
 
   if (BuiltinID == AArch64::BI__builtin_arm_prefetch) {
     return SemaBuiltinConstantArgRange(TheCall, 1, 0, 1) ||
-      SemaBuiltinConstantArgRange(TheCall, 2, 0, 2) ||
-      SemaBuiltinConstantArgRange(TheCall, 3, 0, 1) ||
-      SemaBuiltinConstantArgRange(TheCall, 4, 0, 1);
+           SemaBuiltinConstantArgRange(TheCall, 2, 0, 3) ||
+           SemaBuiltinConstantArgRange(TheCall, 3, 0, 1) ||
+           SemaBuiltinConstantArgRange(TheCall, 4, 0, 1);
   }
 
   if (BuiltinID == AArch64::BI__builtin_arm_rsr64 ||