From 00a6bcaeb4a74b930bc2b21f8021c3358d507ecf Mon Sep 17 00:00:00 2001
From: Nadav Rotem <nrotem@apple.com>
Date: Wed, 2 Jan 2013 23:54:43 +0000
Subject: [PATCH] Avoid vectorization when the function has the
 "noimplicitflot" attribute.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171429 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Transforms/Vectorize/LoopVectorize.cpp | 14 +++++++++++---
 test/Transforms/LoopVectorize/nofloat.ll   | 29 +++++++++++++++++++++++++++++
 2 files changed, 40 insertions(+), 3 deletions(-)
 create mode 100644 test/Transforms/LoopVectorize/nofloat.ll

diff --git a/lib/Transforms/Vectorize/LoopVectorize.cpp b/lib/Transforms/Vectorize/LoopVectorize.cpp
index f2004524b80..9b1d398cccb 100644
--- a/lib/Transforms/Vectorize/LoopVectorize.cpp
+++ b/lib/Transforms/Vectorize/LoopVectorize.cpp
@@ -94,9 +94,17 @@ struct LoopVectorize : public LoopPass {
     // Check the function attribues to find out if this function should be
     // optimized for size.
     Function *F = L->getHeader()->getParent();
-    Attribute::AttrKind SzAttr= Attribute::OptimizeForSize;
-    bool OptForSize =
-      F->getAttributes().hasAttribute(AttributeSet::FunctionIndex, SzAttr);
+    Attribute::AttrKind SzAttr = Attribute::OptimizeForSize;
+    Attribute::AttrKind FlAttr = Attribute::NoImplicitFloat;
+    unsigned FnIndex = AttributeSet::FunctionIndex;
+    bool OptForSize = F->getAttributes().hasAttribute(FnIndex, SzAttr);
+    bool NoFloat = F->getAttributes().hasAttribute(FnIndex, FlAttr);
+
+    if (NoFloat) {
+      DEBUG(dbgs() << "LV: Can't vectorize when the NoImplicitFloat"
+            "attribute is used.\n");
+      return false;
+    }
 
     unsigned VF = CM.selectVectorizationFactor(OptForSize, VectorizationFactor);
 
diff --git a/test/Transforms/LoopVectorize/nofloat.ll b/test/Transforms/LoopVectorize/nofloat.ll
new file mode 100644
index 00000000000..5d27106d888
--- /dev/null
+++ b/test/Transforms/LoopVectorize/nofloat.ll
@@ -0,0 +1,29 @@
+; RUN: opt < %s  -loop-vectorize -force-vector-width=4 -dce -instcombine -licm -S | FileCheck %s
+
+; Make sure that we don't vectorize functions with 'noimplicitfloat' attributes.
+
+target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64-S128"
+target triple = "x86_64-apple-macosx10.8.0"
+
+@a = common global [2048 x i32] zeroinitializer, align 16
+
+;CHECK: @example12
+;CHECK-NOT: store <4 x i32>
+;CHECK: ret void
+define void @example12() noimplicitfloat { ;           <--------- "noimplicitfloat" attribute here!
+  br label %1
+
+; <label>:1                                       ; preds = %1, %0
+  %indvars.iv = phi i64 [ 0, %0 ], [ %indvars.iv.next, %1 ]
+  %2 = getelementptr inbounds [2048 x i32]* @a, i64 0, i64 %indvars.iv
+  %3 = trunc i64 %indvars.iv to i32
+  store i32 %3, i32* %2, align 4
+  %indvars.iv.next = add i64 %indvars.iv, 1
+  %lftr.wideiv = trunc i64 %indvars.iv.next to i32
+  %exitcond = icmp eq i32 %lftr.wideiv, 1024
+  br i1 %exitcond, label %4, label %1
+
+; <label>:4                                       ; preds = %1
+  ret void
+}
+
-- 
2.11.0