From aebd138996c29589d44d6eccea659757c6184b44 Mon Sep 17 00:00:00 2001
From: Sanjoy Das <sanjoy@playingwithpointers.com>
Date: Mon, 24 Apr 2017 20:12:10 +0000
Subject: [PATCH 3/5] [LIR] Obey non-integral pointer semantics

Summary: See http://llvm.org/docs/LangRef.html#non-integral-pointer-type

Reviewers: haicheng

Reviewed By: haicheng

Subscribers: mcrosier, mzolotukhin, llvm-commits

Differential Revision: https://reviews.llvm.org/D32196

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@301238 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Transforms/Scalar/LoopIdiomRecognize.cpp       |  5 +++
 test/Transforms/LoopIdiom/non-integral-pointers.ll | 48 ++++++++++++++++++++++
 2 files changed, 53 insertions(+)
 create mode 100644 test/Transforms/LoopIdiom/non-integral-pointers.ll

diff --git a/lib/Transforms/Scalar/LoopIdiomRecognize.cpp b/lib/Transforms/Scalar/LoopIdiomRecognize.cpp
index 5fec51c095d..570c55a3e76 100644
--- a/lib/Transforms/Scalar/LoopIdiomRecognize.cpp
+++ b/lib/Transforms/Scalar/LoopIdiomRecognize.cpp
@@ -345,6 +345,11 @@ bool LoopIdiomRecognize::isLegalStore(StoreInst *SI, bool &ForMemset,
   if (!SI->isSimple())
     return false;
 
+  // Don't convert stores of non-integral pointer types to memsets (which stores
+  // integers).
+  if (DL->isNonIntegralPointerType(SI->getValueOperand()->getType()))
+    return false;
+
   // Avoid merging nontemporal stores.
   if (SI->getMetadata(LLVMContext::MD_nontemporal))
     return false;
diff --git a/test/Transforms/LoopIdiom/non-integral-pointers.ll b/test/Transforms/LoopIdiom/non-integral-pointers.ll
new file mode 100644
index 00000000000..7646d5ac72d
--- /dev/null
+++ b/test/Transforms/LoopIdiom/non-integral-pointers.ll
@@ -0,0 +1,48 @@
+; RUN: opt -S -basicaa -loop-idiom < %s | FileCheck %s
+
+target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128-ni:4"
+target triple = "x86_64-unknown-linux-gnu"
+
+define void @f_0(i8 addrspace(3)** %ptr) {
+; CHECK-LABEL: @f_0(
+; CHECK: call{{.*}}memset
+
+; LIR'ing stores of pointers with address space 3 is fine, since
+; they're integral pointers.
+
+entry:
+  br label %for.body
+
+for.body:
+  %indvar = phi i64 [ 0, %entry ], [ %indvar.next, %for.body ]
+  %arrayidx = getelementptr i8 addrspace(3)*, i8 addrspace(3)** %ptr, i64 %indvar
+  store i8 addrspace(3)* null, i8 addrspace(3)** %arrayidx, align 4
+  %indvar.next = add i64 %indvar, 1
+  %exitcond = icmp eq i64 %indvar.next, 10000
+  br i1 %exitcond, label %for.end, label %for.body
+
+for.end:
+  ret void
+}
+
+define void @f_1(i8 addrspace(4)** %ptr) {
+; CHECK-LABEL: @f_1(
+; CHECK-NOT: call{{.*}}memset
+
+; LIR'ing stores of pointers with address space 4 is not ok, since
+; they're non-integral pointers.
+
+entry:
+  br label %for.body
+
+for.body:
+  %indvar = phi i64 [ 0, %entry ], [ %indvar.next, %for.body ]
+  %arrayidx = getelementptr i8 addrspace(4)*, i8 addrspace(4)** %ptr, i64 %indvar
+  store i8 addrspace(4)* null, i8 addrspace(4)** %arrayidx, align 4
+  %indvar.next = add i64 %indvar, 1
+  %exitcond = icmp eq i64 %indvar.next, 10000
+  br i1 %exitcond, label %for.end, label %for.body
+
+for.end:
+  ret void
+}
-- 
2.13.1