3 files changed, 150 insertions, 8 deletions
diff --git a/llvm/test/Transforms/LICM/argmemonly-call.ll b/llvm/test/Transforms/LICM/argmemonly-call.ll
index fe7c6af6d6d..b7d7d6a3953 100644
--- a/llvm/test/Transforms/LICM/argmemonly-call.ll
+++ b/llvm/test/Transforms/LICM/argmemonly-call.ll
@@ -1,5 +1,8 @@
-; RUN: opt -S -basicaa -licm %s | FileCheck %s
-; RUN: opt -aa-pipeline=basic-aa -passes='require<aa>,require<targetir>,require<scalar-evolution>,require<opt-remark-emit>,loop(licm)' < %s -S | FileCheck %s
+; RUN: opt -S -basicaa -licm -licm-n2-threshold=0 %s | FileCheck %s
+; RUN: opt -licm -basicaa -licm-n2-threshold=200 < %s -S | FileCheck %s --check-prefix=ALIAS-N2
+; RUN: opt -aa-pipeline=basic-aa -licm-n2-threshold=0 -passes='require<aa>,require<targetir>,require<scalar-evolution>,require<opt-remark-emit>,loop(licm)' < %s -S | FileCheck %s
+; RUN: opt -aa-pipeline=basic-aa -licm-n2-threshold=200 -passes='require<aa>,require<targetir>,require<scalar-evolution>,require<opt-remark-emit>,loop(licm)' < %s -S | FileCheck %s --check-prefix=ALIAS-N2
+
 declare i32 @foo() readonly argmemonly nounwind
 declare i32 @foo2() readonly nounwind
 declare i32 @bar(i32* %loc2) readonly argmemonly nounwind
@@ -68,3 +71,27 @@ loop:
   store i32 %res, i32* %loc
   br label %loop
 }
+
+declare i32 @foo_new(i32*) readonly
+; With the default AST mechanism used by LICM for alias analysis,
+; we clump foo_new with bar.
+; With the N2 Alias analysis diagnostic tool, we are able to hoist the
+; argmemonly bar call out of the loop.
+
+define void @test5(i32* %loc2, i32* noalias %loc) {
+; ALIAS-N2-LABEL: @test5
+; ALIAS-N2: @bar
+; ALIAS-N2-LABEL: loop:
+
+; CHECK-LABEL: @test5
+; CHECK-LABEL: loop:
+; CHECK:  @bar
+  br label %loop
+
+loop:
+  %res1 = call i32 @bar(i32* %loc2)
+  %res = call i32 @foo_new(i32* %loc2)
+  store volatile i32 %res1, i32* %loc
+  br label %loop
+}
+
diff --git a/llvm/test/Transforms/LICM/invariant.start.ll b/llvm/test/Transforms/LICM/invariant.start.ll
index ff17bd096ce..3ac6793d185 100644
--- a/llvm/test/Transforms/LICM/invariant.start.ll
+++ b/llvm/test/Transforms/LICM/invariant.start.ll
@@ -1,7 +1,9 @@
-; RUN: opt -licm -basicaa < %s -S | FileCheck %s
-; RUN: opt -aa-pipeline=basic-aa -passes='require<aa>,require<targetir>,require<scalar-evolution>,require<opt-remark-emit>,loop(licm)' < %s -S | FileCheck %s
+; RUN: opt -licm -basicaa -licm-n2-threshold=0 < %s -S | FileCheck %s
+; RUN: opt -licm -basicaa -licm-n2-threshold=200 < %s -S | FileCheck %s --check-prefix=ALIAS-N2
+; RUN: opt -aa-pipeline=basic-aa -licm-n2-threshold=0 -passes='require<aa>,require<targetir>,require<scalar-evolution>,require<opt-remark-emit>,loop(licm)' < %s -S | FileCheck %s
+; RUN: opt -aa-pipeline=basic-aa -licm-n2-threshold=200 -passes='require<aa>,require<targetir>,require<scalar-evolution>,require<opt-remark-emit>,loop(licm)' < %s -S | FileCheck %s --check-prefix=ALIAS-N2
 
-; TODO: should be able to hoist both load and invariant.start
+; TODO: By default (without the -licm-n2-threshold value), we should be able to hoist both load and invariant.start
 define void @test1(i1 %cond, i32* %ptr) {
 ; CHECK-LABEL: @test1(
 ; CHECK-LABEL: entry:
@@ -9,6 +11,12 @@ define void @test1(i1 %cond, i32* %ptr) {
 ; CHECK: call {}* @llvm.invariant.start.p0i32(i64 4, i32* %ptr)
 ; CHECK: %val = load i32, i32* %ptr
 
+; ALIAS-N2-LABEL: @test1(
+; ALIAS-N2-LABEL: entry:
+; ALIAS-N2:         %val = load i32, i32* %ptr
+; ALIAS-N2-LABEL: loop:
+; ALIAS-N2: call {}* @llvm.invariant.start.p0i32(i64 4, i32* %ptr)
+
 entry:
   br label %loop
 
@@ -20,7 +28,7 @@ loop:
   br label %loop
 }
 
-;; TODO: despite the loop varying invariant.start, we should be
+;; TODO: By default, despite the loop varying invariant.start, we should be
 ;; able to hoist the load
 define void @test2(i1 %cond, i32* %ptr) {
 ; CHECK-LABEL: @test2(
@@ -28,7 +36,12 @@ define void @test2(i1 %cond, i32* %ptr) {
 ; CHECK-LABEL: loop:
 ; CHECK: call {}* @llvm.invariant.start.p0i32(i64 4, i32* %piv)
 ; CHECK: %val = load i32, i32* %ptr
-  
+
+; ALIAS-N2-LABEL: @test2(
+; ALIAS-N2-LABEL: entry:
+; ALIAS-N2:         %val = load i32, i32* %ptr
+; ALIAS-N2-LABEL: loop:
+; ALIAS-N2:         call {}* @llvm.invariant.start.p0i32(i64 4, i32* %piv)
 entry:
   br label %loop
 
@@ -41,7 +54,7 @@ loop:
   br label %loop
 }
 
-; Should be able to hoist since store doesn't alias
+; By default, should be able to hoist since store doesn't alias
 define void @test3(i1 %cond, i32* %ptr) {
 ; CHECK-LABEL: @test3(
 ; CHECK-LABEL: entry:
@@ -49,6 +62,11 @@ define void @test3(i1 %cond, i32* %ptr) {
 ; CHECK: call {}* @llvm.invariant.start.p0i32(i64 4, i32* %ptr)
 ; CHECK: %val = load i32, i32* %ptr
 
+; ALIAS-N2-LABEL: @test3(
+; ALIAS-N2-LABEL: entry:
+; ALIAS-N2:         %val = load i32, i32* %ptr
+; ALIAS-N2-LABEL: loop:
+; ALIAS-N2:         call {}* @llvm.invariant.start.p0i32(i64 4, i32* %ptr)
 entry:
   br label %loop
 
@@ -72,6 +90,12 @@ define void @test4(i1 %cond, i32* %ptr) {
 ; CHECK: call {}* @llvm.invariant.start.p0i32(i64 4, i32* %ptr)
 ; CHECK: %val = load i32, i32* %ptr
 
+; ALIAS-N2-LABEL: @test4(
+; ALIAS-N2-LABEL: entry:
+; ALIAS-N2-LABEL: loop:
+; ALIAS-N2:   store i32 0, i32* %ptr
+; ALIAS-N2: call {}* @llvm.invariant.start.p0i32(i64 4, i32* %ptr)
+; ALIAS-N2: %val = load i32, i32* %ptr
 entry:
   br label %loop
 
@@ -93,6 +117,12 @@ define void @test5(i1 %cond, i32* %ptr) {
 ; CHECK: call {}* @llvm.invariant.start.p0i32(i64 4, i32* %ptr)
 ; CHECK: %val = load i32, i32* %ptr
 
+; ALIAS-N2-LABEL: @test5(
+; ALIAS-N2-LABEL: entry:
+; ALIAS-N2-LABEL: loop:
+; ALIAS-N2:   store i32 0, i32* %ptr
+; ALIAS-N2: call {}* @llvm.invariant.start.p0i32(i64 4, i32* %ptr)
+; ALIAS-N2: %val = load i32, i32* %ptr
 entry:
   br label %loop
 
diff --git a/llvm/test/Transforms/LICM/read-only-calls.ll b/llvm/test/Transforms/LICM/read-only-calls.ll
new file mode 100644
index 00000000000..0a378144fb7
--- /dev/null
+++ b/llvm/test/Transforms/LICM/read-only-calls.ll
@@ -0,0 +1,85 @@
+; RUN: opt -S -basicaa -licm -licm-n2-threshold=0 %s | FileCheck %s
+; RUN: opt -licm -basicaa -licm-n2-threshold=200 < %s -S | FileCheck %s --check-prefix=ALIAS-N2
+; RUN: opt -aa-pipeline=basic-aa -licm-n2-threshold=0 -passes='require<aa>,require<targetir>,require<scalar-evolution>,require<opt-remark-emit>,loop(licm)' < %s -S | FileCheck %s
+; RUN: opt -aa-pipeline=basic-aa -licm-n2-threshold=200 -passes='require<aa>,require<targetir>,require<scalar-evolution>,require<opt-remark-emit>,loop(licm)' < %s -S | FileCheck %s --check-prefix=ALIAS-N2
+
+; We should be able to hoist loads in presence of read only calls and stores
+; that do not alias.
+
+; Since LICM uses the AST mechanism for alias analysis, we will clump
+; together all loads and stores in one set along with the read-only call.
+; This prevents hoisting load that doesn't alias with any other memory
+; operations.
+
+declare void @foo(i64, i32*) readonly
+
+; hoist the load out with the n2-threshold
+; since it doesn't alias with the store.
+; default AST mechanism clumps all memory locations in one set because of the
+; readonly call
+define void @test1(i32* %ptr) {
+; CHECK-LABEL: @test1(
+; CHECK-LABEL: entry:
+; CHECK-LABEL: loop:
+; CHECK: %val = load i32, i32* %ptr
+
+; ALIAS-N2-LABEL: @test1(
+; ALIAS-N2-LABEL: entry:
+; ALIAS-N2:         %val = load i32, i32* %ptr
+; ALIAS-N2-LABEL: loop:
+entry:
+  br label %loop
+
+loop:
+  %x = phi i32 [ 0, %entry ], [ %x.inc, %loop ]
+  %val = load i32, i32* %ptr
+  call void @foo(i64 4, i32* %ptr)
+  %p2 = getelementptr i32, i32* %ptr, i32 1
+  store volatile i32 0, i32* %p2
+  %x.inc = add i32 %x, %val
+  br label %loop
+}
+
+; can hoist out load with the default AST and the alias analysis mechanism.
+define void @test2(i32* %ptr) {
+; CHECK-LABEL: @test2(
+; CHECK-LABEL: entry:
+; CHECK: %val = load i32, i32* %ptr
+; CHECK-LABEL: loop:
+
+; ALIAS-N2-LABEL: @test2(
+; ALIAS-N2-LABEL: entry:
+; ALIAS-N2:         %val = load i32, i32* %ptr
+; ALIAS-N2-LABEL: loop:
+entry:
+  br label %loop
+
+loop:
+  %x = phi i32 [ 0, %entry ], [ %x.inc, %loop ]
+  %val = load i32, i32* %ptr
+  call void @foo(i64 4, i32* %ptr)
+  %x.inc = add i32 %x, %val
+  br label %loop
+}
+
+; cannot hoist load since not guaranteed to execute
+define void @test3(i32* %ptr) {
+; CHECK-LABEL: @test3(
+; CHECK-LABEL: entry:
+; CHECK-LABEL: loop:
+; CHECK: %val = load i32, i32* %ptr
+
+; ALIAS-N2-LABEL: @test3(
+; ALIAS-N2-LABEL: entry:
+; ALIAS-N2-LABEL: loop:
+; ALIAS-N2:         %val = load i32, i32* %ptr
+entry:
+  br label %loop
+
+loop:
+  %x = phi i32 [ 0, %entry ], [ %x.inc, %loop ]
+  call void @foo(i64 4, i32* %ptr)
+  %val = load i32, i32* %ptr
+  %x.inc = add i32 %x, %val
+  br label %loop
+}