From 2c71fc8bb7f9c38d0ed1855efee601fa9dc0a45a Mon Sep 17 00:00:00 2001
From: Justin Lebar <jlebar@google.com>
Date: Sun, 11 Sep 2016 01:39:08 +0000
Subject: [PATCH] Add handling of !invariant.load to PropagateMetadata.

Summary:
This will let e.g. the load/store vectorizer propagate this metadata
appropriately.

Reviewers: arsenm

Subscribers: tra, jholewinski, hfinkel, mzolotukhin

Differential Revision: https://reviews.llvm.org/D23479

llvm-svn: 281153
---
 lib/Analysis/VectorUtils.cpp                    | 12 ++++++------
 .../NVPTX/propagate-invariance-metadata.ll      | 17 +++++++++++++++++
 2 files changed, 23 insertions(+), 6 deletions(-)
 create mode 100644 test/Transforms/LoadStoreVectorizer/NVPTX/propagate-invariance-metadata.ll

diff --git a/lib/Analysis/VectorUtils.cpp b/lib/Analysis/VectorUtils.cpp
index 53e7153a350..5a51fd8a524 100644
--- a/lib/Analysis/VectorUtils.cpp
+++ b/lib/Analysis/VectorUtils.cpp
@@ -454,9 +454,10 @@ Instruction *llvm::propagateMetadata(Instruction *Inst, ArrayRef<Value *> VL) {
   SmallVector<std::pair<unsigned, MDNode *>, 4> Metadata;
   I0->getAllMetadataOtherThanDebugLoc(Metadata);
 
-  for (auto Kind : { LLVMContext::MD_tbaa, LLVMContext::MD_alias_scope,
-                     LLVMContext::MD_noalias, LLVMContext::MD_fpmath,
-                     LLVMContext::MD_nontemporal }) {
+  for (auto Kind :
+       {LLVMContext::MD_tbaa, LLVMContext::MD_alias_scope,
+        LLVMContext::MD_noalias, LLVMContext::MD_fpmath,
+        LLVMContext::MD_nontemporal, LLVMContext::MD_invariant_load}) {
     MDNode *MD = I0->getMetadata(Kind);
 
     for (int J = 1, E = VL.size(); MD && J != E; ++J) {
@@ -469,13 +470,12 @@ Instruction *llvm::propagateMetadata(Instruction *Inst, ArrayRef<Value *> VL) {
       case LLVMContext::MD_alias_scope:
         MD = MDNode::getMostGenericAliasScope(MD, IMD);
         break;
-      case LLVMContext::MD_noalias:
-        MD = MDNode::intersect(MD, IMD);
-        break;
       case LLVMContext::MD_fpmath:
         MD = MDNode::getMostGenericFPMath(MD, IMD);
         break;
+      case LLVMContext::MD_noalias:
       case LLVMContext::MD_nontemporal:
+      case LLVMContext::MD_invariant_load:
         MD = MDNode::intersect(MD, IMD);
         break;
       default:
diff --git a/test/Transforms/LoadStoreVectorizer/NVPTX/propagate-invariance-metadata.ll b/test/Transforms/LoadStoreVectorizer/NVPTX/propagate-invariance-metadata.ll
new file mode 100644
index 00000000000..ac0660e7833
--- /dev/null
+++ b/test/Transforms/LoadStoreVectorizer/NVPTX/propagate-invariance-metadata.ll
@@ -0,0 +1,17 @@
+; RUN: opt -load-store-vectorizer -march=nvptx64 -mcpu=sm_35 -S < %s | FileCheck %s
+
+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-v16:16:16-v32:32:32-v64:64:64-v128:128:128-n16:32:64"
+target triple = "nvptx64-nvidia-cuda"
+
+; CHECK-LABEL: @foo
+define i32 @foo(i32* %ptr) {
+  %ptr1 = getelementptr i32, i32* %ptr, i32 1
+  %p1 = addrspacecast i32* %ptr1 to i32 addrspace(1)*
+  ; CHECK: load <2 x i32>, <2 x i32>* %{{[0-9]+}}, align 8, !invariant.load !0
+  %v0 = load i32, i32* %ptr, align 8, !invariant.load !0
+  %v1 = load i32, i32* %ptr1, align 4, !invariant.load !0
+  %sum = add i32 %v0, %v1
+  ret i32 %sum
+}
+
+!0 = !{}