From: Joel Jones <joel_k_jones@apple.com>
Date: Fri, 13 Jul 2012 23:26:27 +0000 (+0000)
Subject: This is one of the first steps at moving to replace target-dependent
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=87d747b1fbf89aa0ba08cfc0e26655aa7739c77d;p=clang

This is one of the first steps at moving to replace target-dependent
intrinsics with target-indepdent intrinsics.  The first instruction(s) to be
handled are the vector versions of count leading zeros (ctlz).

The changes here are to clang so that it generates a target independent
vector ctlz when it sees an ARM dependent vector ctlz.  The changes in llvm
are to match the target independent vector ctlz and in VMCore/AutoUpgrade.cpp
to update any existing bc files containing ARM dependent vector ctlzs with
target-independent ctlzs.  There are also changes to an existing test case in
llvm for ARM vector count instructions and a new test for the bitcode upgrade.

<rdar://problem/11831778>

There is deliberately no test for the change to clang, as so far as I know, no
consensus has been reached regarding how to test neon instructions in clang;
q.v. <rdar://problem/8762292>


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@160201 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/CodeGen/CGBuiltin.cpp b/lib/CodeGen/CGBuiltin.cpp
index 575fa5d1ac..d8fdad6453 100644
--- a/lib/CodeGen/CGBuiltin.cpp
+++ b/lib/CodeGen/CGBuiltin.cpp
@@ -1629,7 +1629,10 @@ Value *CodeGenFunction::EmitARMBuiltinExpr(unsigned BuiltinID,
   }
   case ARM::BI__builtin_neon_vclz_v:
   case ARM::BI__builtin_neon_vclzq_v: {
-    Function *F = CGM.getIntrinsic(Intrinsic::arm_neon_vclz, Ty);
+    // generate target-independent intrinsic; also need to add second argument
+    // for whether or not clz of zero is undefined; on ARM it isn't.
+    Function *F = CGM.getIntrinsic(Intrinsic::ctlz, Ty);
+    Ops.push_back(Builder.getInt1(Target.isCLZForZeroUndef()));
     return EmitNeonCall(F, Ops, "vclz");
   }
   case ARM::BI__builtin_neon_vcnt_v: