[AArch64] Add support for MTE intrinsics

This provides intrinsics support for Memory Tagging Extension (MTE),
which was introduced with the Armv8.5-a architecture.
These intrinsics are available when __ARM_FEATURE_MEMORY_TAGGING is defined.
Each intrinsic is described in detail in the ACLE Q1 2019 documentation:
https://developer.arm.com/docs/101028/latest
Reviewed By: Tim Nortover, David Spickett
Differential Revision: https://reviews.llvm.org/D60485

llvm-svn: 359348

1 files changed, 78 insertions, 0 deletions

diff --git a/clang/lib/CodeGen/CGBuiltin.cpp b/clang/lib/CodeGen/CGBuiltin.cpp
index cfdb69c0798..bc5f6cfe43e 100644
--- a/clang/lib/CodeGen/CGBuiltin.cpp
+++ b/clang/lib/CodeGen/CGBuiltin.cpp
@@ -7077,6 +7077,84 @@ Value *CodeGenFunction::EmitAArch64BuiltinExpr(unsigned BuiltinID,
     return Builder.CreateCall(F, {Arg0, Arg1});
   }
 
+  // Memory Tagging Extensions (MTE) Intrinsics
+  Intrinsic::ID MTEIntrinsicID = Intrinsic::not_intrinsic;
+  switch (BuiltinID) {
+  case AArch64::BI__builtin_arm_irg:
+    MTEIntrinsicID = Intrinsic::aarch64_irg; break;
+  case  AArch64::BI__builtin_arm_addg:
+    MTEIntrinsicID = Intrinsic::aarch64_addg; break;
+  case  AArch64::BI__builtin_arm_gmi:
+    MTEIntrinsicID = Intrinsic::aarch64_gmi; break;
+  case  AArch64::BI__builtin_arm_ldg:
+    MTEIntrinsicID = Intrinsic::aarch64_ldg; break;
+  case AArch64::BI__builtin_arm_stg:
+    MTEIntrinsicID = Intrinsic::aarch64_stg; break;
+  case AArch64::BI__builtin_arm_subp:
+    MTEIntrinsicID = Intrinsic::aarch64_subp; break;
+  }
+
+  if (MTEIntrinsicID != Intrinsic::not_intrinsic) {
+    llvm::Type *T = ConvertType(E->getType());
+
+    if (MTEIntrinsicID == Intrinsic::aarch64_irg) {
+      Value *Pointer = EmitScalarExpr(E->getArg(0));
+      Value *Mask = EmitScalarExpr(E->getArg(1));
+
+      Pointer = Builder.CreatePointerCast(Pointer, Int8PtrTy);
+      Mask = Builder.CreateZExt(Mask, Int64Ty);
+      Value *RV = Builder.CreateCall(
+                       CGM.getIntrinsic(MTEIntrinsicID), {Pointer, Mask});
+       return Builder.CreatePointerCast(RV, T);
+    }
+    if (MTEIntrinsicID == Intrinsic::aarch64_addg) {
+      Value *Pointer = EmitScalarExpr(E->getArg(0));
+      Value *TagOffset = EmitScalarExpr(E->getArg(1));
+
+      Pointer = Builder.CreatePointerCast(Pointer, Int8PtrTy);
+      TagOffset = Builder.CreateZExt(TagOffset, Int64Ty);
+      Value *RV = Builder.CreateCall(
+                       CGM.getIntrinsic(MTEIntrinsicID), {Pointer, TagOffset});
+      return Builder.CreatePointerCast(RV, T);
+    }
+    if (MTEIntrinsicID == Intrinsic::aarch64_gmi) {
+      Value *Pointer = EmitScalarExpr(E->getArg(0));
+      Value *ExcludedMask = EmitScalarExpr(E->getArg(1));
+
+      ExcludedMask = Builder.CreateZExt(ExcludedMask, Int64Ty);
+      Pointer = Builder.CreatePointerCast(Pointer, Int8PtrTy);
+      return Builder.CreateCall(
+                       CGM.getIntrinsic(MTEIntrinsicID), {Pointer, ExcludedMask});
+    }
+    // Although it is possible to supply a different return
+    // address (first arg) to this intrinsic, for now we set
+    // return address same as input address.
+    if (MTEIntrinsicID == Intrinsic::aarch64_ldg) {
+      Value *TagAddress = EmitScalarExpr(E->getArg(0));
+      TagAddress = Builder.CreatePointerCast(TagAddress, Int8PtrTy);
+      Value *RV = Builder.CreateCall(
+                    CGM.getIntrinsic(MTEIntrinsicID), {TagAddress, TagAddress});
+      return Builder.CreatePointerCast(RV, T);
+    }
+    // Although it is possible to supply a different tag (to set)
+    // to this intrinsic (as first arg), for now we supply
+    // the tag that is in input address arg (common use case).
+    if (MTEIntrinsicID == Intrinsic::aarch64_stg) {
+        Value *TagAddress = EmitScalarExpr(E->getArg(0));
+        TagAddress = Builder.CreatePointerCast(TagAddress, Int8PtrTy);
+        return Builder.CreateCall(
+                 CGM.getIntrinsic(MTEIntrinsicID), {TagAddress, TagAddress});
+    }
+    if (MTEIntrinsicID == Intrinsic::aarch64_subp) {
+      Value *PointerA = EmitScalarExpr(E->getArg(0));
+      Value *PointerB = EmitScalarExpr(E->getArg(1));
+      PointerA = Builder.CreatePointerCast(PointerA, Int8PtrTy);
+      PointerB = Builder.CreatePointerCast(PointerB, Int8PtrTy);
+      return Builder.CreateCall(
+                       CGM.getIntrinsic(MTEIntrinsicID), {PointerA, PointerB});
+    }
+  }
+
   if (BuiltinID == AArch64::BI__builtin_arm_rsr ||
       BuiltinID == AArch64::BI__builtin_arm_rsr64 ||
       BuiltinID == AArch64::BI__builtin_arm_rsrp ||