Subzero: Loop Invariant Code Motion

tests_lit/llvm2ice_tests/licm.ll

Index: tests_lit/llvm2ice_tests/licm.ll
diff --git a/tests_lit/llvm2ice_tests/licm.ll b/tests_lit/llvm2ice_tests/licm.ll
new file mode 100644
index 0000000000000000000000000000000000000000..53761bb36ce90ec618572378670d4a0cfb44e3ca
--- /dev/null
+++ b/tests_lit/llvm2ice_tests/licm.ll
@@ -0,0 +1,36 @@
+; Tests if the licm flag successfully hoists the add from loop0 to entry
+
+; RUN: %p2i -i %s --filetype=obj --disassemble --target x8664 --args \
+; RUN: -O2 -licm | FileCheck --check-prefix ENABLE %s
+
+; RUN: %p2i -i %s --filetype=obj --disassemble --target x8664 --args \
+; RUN: -O2 | FileCheck --check-prefix NOENABLE %s
+
+define internal void @dummy() {
+entry:
+  ret void
+}
+define internal i32 @test_licm(i32 %a32, i32 %b, i32 %c) {
+entry:
+  %a = trunc i32 %a32 to i1
+  br label %loop0
+loop0:                               ; <-+
+  call void @dummy()                 ;   |
+  %add1 = add i32 %b, %c             ;   |
+  br label %loop1                    ;   |
+loop1:                               ;   |
+  br i1 %a, label %loop0, label %out ; --+
+out:
+  ret i32 %add1
+}
+
+; CHECK-LABEL: test_licm
+
+; ENABLE: add
+; ENABLE: call
+
+; NOENABLE: call
+; NOENABLE-NEXT: mov
+; NOENABLE-NEXT: add
+
+; CHECK: ret