Add an inlining debuginfo test

src/test/codegen/inline-debuginfo.rs

@@ -0,0 +1,16 @@
+#![crate_type="rlib"]
+// compile-flags: -Copt-level=3 -g
+
+#[no_mangle]
+#[inline(always)]
+pub extern "C" fn callee(x: u32) -> u32 {
+    x + 4
+}
+
+// CHECK-LABEL: caller
+// CHECK: call void @llvm.dbg.value(metadata i32 %y, metadata !{{.*}}, metadata !DIExpression(DW_OP_constu, 3, DW_OP_minus, DW_OP_stack_value)), !dbg [[A:!.*]]
+// CHECK: [[A]] = !DILocation(line: {{.*}}, scope: {{.*}}, inlinedAt: {{.*}})
+#[no_mangle]
+pub extern "C" fn caller(y: u32) -> u32 {
+    callee(y - 3)
+}