[ARM] Enabling range checks on Neon intrinsics' lane arguments

Summary:
Range checks were not properly performed in the lane arguments of Neon
intrinsics implemented based on splat operations. Calls to those
intrinsics where translated to `__builtin__shufflevector` calls directly
by the pre-processor through the arm_neon.h macros, missing the chance
for the proper range checks.

This patch enables the range check by introducing an auxiliary splat
instruction in arm_neon.td, delaying the translation to shufflevector
calls to CGBuiltin.cpp in clang after the checks were performed.

Reviewers: jmolloy, t.p.northover, rsmith, olista01, ostannard

Reviewed By: ostannard

Subscribers: ostannard, dnsampaio, danielkiss, kristof.beyls, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D74619

1 files changed, 2 insertions, 0 deletions

diff --git a/clang/lib/CodeGen/CodeGenFunction.h b/clang/lib/CodeGen/CodeGenFunction.h
index 440b088..0128a07 100644
--- a/clang/lib/CodeGen/CodeGenFunction.h
+++ b/clang/lib/CodeGen/CodeGenFunction.h
@@ -3894,6 +3894,8 @@ public:
                             SmallVectorImpl<llvm::Value*> &O,
                             const char *name,
                             unsigned shift = 0, bool rightshift = false);
+  llvm::Value *EmitNeonSplat(llvm::Value *V, llvm::Constant *Idx,
+                             const llvm::ElementCount &Count);
   llvm::Value *EmitNeonSplat(llvm::Value *V, llvm::Constant *Idx);
   llvm::Value *EmitNeonShiftVector(llvm::Value *V, llvm::Type *Ty,
                                    bool negateForRightShift);