1 files changed, 47 insertions, 0 deletions
diff --git a/llvm/test/CodeGen/WebAssembly/reg-stackify.ll b/llvm/test/CodeGen/WebAssembly/reg-stackify.ll
new file mode 100644
index 00000000000..f3000aab70a
--- /dev/null
+++ b/llvm/test/CodeGen/WebAssembly/reg-stackify.ll
@@ -0,0 +1,47 @@
+; RUN: llc < %s -asm-verbose=false | FileCheck %s
+
+; Test the register stackifier pass.
+
+target datalayout = "e-p:32:32-i64:64-n32:64-S128"
+target triple = "wasm32-unknown-unknown"
+
+; No because of pointer aliasing.
+
+; CHECK-LABEL: no0:
+; CHECK: return $1{{$}}
+define i32 @no0(i32* %p, i32* %q) {
+  %t = load i32, i32* %q
+  store i32 0, i32* %p
+  ret i32 %t
+}
+
+; No because of side effects.
+
+; CHECK-LABEL: no1:
+; CHECK: return $1{{$}}
+define i32 @no1(i32* %p, i32* dereferenceable(4) %q) {
+  %t = load volatile i32, i32* %q, !invariant.load !0
+  store volatile i32 0, i32* %p
+  ret i32 %t
+}
+
+; Yes because of invariant load and no side effects.
+
+; CHECK-LABEL: yes0:
+; CHECK: return $pop0{{$}}
+define i32 @yes0(i32* %p, i32* dereferenceable(4) %q) {
+  %t = load i32, i32* %q, !invariant.load !0
+  store i32 0, i32* %p
+  ret i32 %t
+}
+
+; Yes because of no intervening side effects.
+
+; CHECK-LABEL: yes1:
+; CHECK: return $pop0{{$}}
+define i32 @yes1(i32* %q) {
+  %t = load volatile i32, i32* %q
+  ret i32 %t
+}
+
+!0 = !{}