Revamp codegen tests to check IR quality instead of quantity

The current codegen tests only compare IR line counts between similar
rust and C programs, the latter getting compiled with clang. That looked
like a good idea back then, but actually things like lifetime intrinsics
mean that less IR isn't always better, so the metric isn't really
helpful.

Instead, we can start doing tests that check specific aspects of the
generated IR, like attributes or metadata. To do that, we can use LLVM's
FileCheck tool which has a number of useful features for such tests.

To start off, I created some tests for a few things that were recently
added and/or broken.

25 files changed, 209 insertions, 524 deletions

diff --git a/mk/tests.mk b/mk/tests.mk
index 44c661c4e20..2f1510ba87c 100644
--- a/mk/tests.mk
+++ b/mk/tests.mk
@@ -581,10 +581,6 @@ ifeq ($(CFG_LLDB),)
 CTEST_DISABLE_debuginfo-lldb = "no lldb found"
 endif
 
-ifeq ($(CFG_CLANG),)
-CTEST_DISABLE_codegen = "no clang found"
-endif
-
 ifneq ($(CFG_OSTYPE),apple-darwin)
 CTEST_DISABLE_debuginfo-lldb = "lldb tests are only run on darwin"
 endif
@@ -645,7 +641,6 @@ CTEST_COMMON_ARGS$(1)-T-$(2)-H-$(3) := \
         --run-lib-path $$(TLIB$(1)_T_$(2)_H_$(3)) \
         --rustc-path $$(HBIN$(1)_H_$(3))/rustc$$(X_$(3)) \
         --rustdoc-path $$(HBIN$(1)_H_$(3))/rustdoc$$(X_$(3)) \
-        --clang-path $(if $(CFG_CLANG),$(CFG_CLANG),clang) \
         --llvm-bin-path $(CFG_LLVM_INST_DIR_$(CFG_BUILD))/bin \
         --aux-base $$(S)src/test/auxiliary/ \
         --stage-id stage$(1)-$(2) \
diff --git a/src/compiletest/common.rs b/src/compiletest/common.rs
index dcac32ccb8a..3f34c89d18f 100644
--- a/src/compiletest/common.rs
+++ b/src/compiletest/common.rs
@@ -80,9 +80,6 @@ pub struct Config {
     // The python executable
     pub python: String,
 
-    // The clang executable
-    pub clang_path: Option<PathBuf>,
-
     // The llvm binaries path
     pub llvm_bin_path: Option<PathBuf>,
 
diff --git a/src/compiletest/compiletest.rs b/src/compiletest/compiletest.rs
index 3ff7f3cc70a..9d575675cc8 100644
--- a/src/compiletest/compiletest.rs
+++ b/src/compiletest/compiletest.rs
@@ -33,7 +33,7 @@ use std::fs;
 use std::path::{Path, PathBuf};
 use getopts::{optopt, optflag, reqopt};
 use common::Config;
-use common::{Pretty, DebugInfoGdb, DebugInfoLldb, Codegen};
+use common::{Pretty, DebugInfoGdb, DebugInfoLldb};
 use util::logv;
 
 pub mod procsrv;
@@ -63,7 +63,6 @@ pub fn parse_config(args: Vec<String> ) -> Config {
           reqopt("", "rustc-path", "path to rustc to use for compiling", "PATH"),
           reqopt("", "rustdoc-path", "path to rustdoc to use for compiling", "PATH"),
           reqopt("", "python", "path to python to use for doc tests", "PATH"),
-          optopt("", "clang-path", "path to  executable for codegen tests", "PATH"),
           optopt("", "valgrind-path", "path to Valgrind executable for Valgrind tests", "PROGRAM"),
           optflag("", "force-valgrind", "fail if Valgrind tests cannot be run under Valgrind"),
           optopt("", "llvm-bin-path", "path to directory holding llvm binaries", "DIR"),
@@ -133,7 +132,6 @@ pub fn parse_config(args: Vec<String> ) -> Config {
         rustc_path: opt_path(matches, "rustc-path"),
         rustdoc_path: opt_path(matches, "rustdoc-path"),
         python: matches.opt_str("python").unwrap(),
-        clang_path: matches.opt_str("clang-path").map(|s| PathBuf::from(&s)),
         valgrind_path: matches.opt_str("valgrind-path"),
         force_valgrind: matches.opt_present("force-valgrind"),
         llvm_bin_path: matches.opt_str("llvm-bin-path").map(|s| PathBuf::from(&s)),
@@ -284,13 +282,7 @@ pub fn make_tests(config: &Config) -> Vec<test::TestDescAndFn> {
         let file = file.unwrap().path();
         debug!("inspecting file {:?}", file.display());
         if is_test(config, &file) {
-            let t = make_test(config, &file, || {
-                match config.mode {
-                    Codegen => make_metrics_test_closure(config, &file),
-                    _ => make_test_closure(config, &file)
-                }
-            });
-            tests.push(t)
+            tests.push(make_test(config, &file))
         }
     }
     tests
@@ -323,8 +315,7 @@ pub fn is_test(config: &Config, testfile: &Path) -> bool {
     return valid;
 }
 
-pub fn make_test<F>(config: &Config, testfile: &Path, f: F) -> test::TestDescAndFn where
-    F: FnOnce() -> test::TestFn,
+pub fn make_test(config: &Config, testfile: &Path) -> test::TestDescAndFn
 {
     test::TestDescAndFn {
         desc: test::TestDesc {
@@ -332,7 +323,7 @@ pub fn make_test<F>(config: &Config, testfile: &Path, f: F) -> test::TestDescAnd
             ignore: header::is_test_ignored(config, testfile),
             should_panic: test::ShouldPanic::No,
         },
-        testfn: f(),
+        testfn: make_test_closure(config, &testfile),
     }
 }
 
@@ -357,14 +348,6 @@ pub fn make_test_closure(config: &Config, testfile: &Path) -> test::TestFn {
     }))
 }
 
-pub fn make_metrics_test_closure(config: &Config, testfile: &Path) -> test::TestFn {
-    let config = (*config).clone();
-    let testfile = testfile.to_path_buf();
-    test::DynMetricFn(box move |mm: &mut test::MetricMap| {
-        runtest::run_metrics(config, &testfile, mm)
-    })
-}
-
 fn extract_gdb_version(full_version_line: Option<String>) -> Option<String> {
     match full_version_line {
         Some(ref full_version_line)
diff --git a/src/compiletest/runtest.rs b/src/compiletest/runtest.rs
index 33d4f761eea..fef36ec2c2f 100644
--- a/src/compiletest/runtest.rs
+++ b/src/compiletest/runtest.rs
@@ -28,8 +28,6 @@ use std::iter::repeat;
 use std::net::TcpStream;
 use std::path::{Path, PathBuf};
 use std::process::{Command, Output, ExitStatus};
-use std::str;
-use test::MetricMap;
 
 pub fn run(config: Config, testfile: &Path) {
     match &*config.target {
@@ -43,11 +41,6 @@ pub fn run(config: Config, testfile: &Path) {
         _=> { }
     }
 
-    let mut _mm = MetricMap::new();
-    run_metrics(config, testfile, &mut _mm);
-}
-
-pub fn run_metrics(config: Config, testfile: &Path, mm: &mut MetricMap) {
     if config.verbose {
         // We're going to be dumping a lot of info. Start on a new line.
         print!("\n\n");
@@ -64,7 +57,7 @@ pub fn run_metrics(config: Config, testfile: &Path, mm: &mut MetricMap) {
         Pretty => run_pretty_test(&config, &props, &testfile),
         DebugInfoGdb => run_debuginfo_gdb_test(&config, &props, &testfile),
         DebugInfoLldb => run_debuginfo_lldb_test(&config, &props, &testfile),
-        Codegen => run_codegen_test(&config, &props, &testfile, mm),
+        Codegen => run_codegen_test(&config, &props, &testfile),
         Rustdoc => run_rustdoc_test(&config, &props, &testfile),
     }
 }
@@ -1685,26 +1678,15 @@ fn _arm_push_aux_shared_library(config: &Config, testfile: &Path) {
     }
 }
 
-// codegen tests (vs. clang)
-
-fn append_suffix_to_stem(p: &Path, suffix: &str) -> PathBuf {
-    if suffix.is_empty() {
-        p.to_path_buf()
-    } else {
-        let mut stem = p.file_stem().unwrap().to_os_string();
-        stem.push("-");
-        stem.push(suffix);
-        p.with_file_name(&stem)
-    }
-}
+// codegen tests (using FileCheck)
 
-fn compile_test_and_save_bitcode(config: &Config, props: &TestProps,
+fn compile_test_and_save_ir(config: &Config, props: &TestProps,
                                  testfile: &Path) -> ProcRes {
     let aux_dir = aux_output_dir_name(config, testfile);
     // FIXME (#9639): This needs to handle non-utf8 paths
     let mut link_args = vec!("-L".to_string(),
                              aux_dir.to_str().unwrap().to_string());
-    let llvm_args = vec!("--emit=llvm-bc,obj".to_string(),
+    let llvm_args = vec!("--emit=llvm-ir".to_string(),
                          "--crate-type=lib".to_string());
     link_args.extend(llvm_args.into_iter());
     let args = make_compile_args(config,
@@ -1717,121 +1699,34 @@ fn compile_test_and_save_bitcode(config: &Config, props: &TestProps,
     compose_and_run_compiler(config, props, testfile, args, None)
 }
 
-fn compile_cc_with_clang_and_save_bitcode(config: &Config, _props: &TestProps,
-                                          testfile: &Path) -> ProcRes {
-    let bitcodefile = output_base_name(config, testfile).with_extension("bc");
-    let bitcodefile = append_suffix_to_stem(&bitcodefile, "clang");
-    let testcc = testfile.with_extension("cc");
-    let proc_args = ProcArgs {
-        // FIXME (#9639): This needs to handle non-utf8 paths
-        prog: config.clang_path.as_ref().unwrap().to_str().unwrap().to_string(),
-        args: vec!("-c".to_string(),
-                   "-emit-llvm".to_string(),
-                   "-o".to_string(),
-                   bitcodefile.to_str().unwrap().to_string(),
-                   testcc.to_str().unwrap().to_string())
-    };
-    compose_and_run(config, testfile, proc_args, Vec::new(), "", None, None)
-}
-
-fn extract_function_from_bitcode(config: &Config, _props: &TestProps,
-                                 fname: &str, testfile: &Path,
-                                 suffix: &str) -> ProcRes {
-    let bitcodefile = output_base_name(config, testfile).with_extension("bc");
-    let bitcodefile = append_suffix_to_stem(&bitcodefile, suffix);
-    let extracted_bc = append_suffix_to_stem(&bitcodefile, "extract");
-    let prog = config.llvm_bin_path.as_ref().unwrap().join("llvm-extract");
+fn check_ir_with_filecheck(config: &Config, testfile: &Path) -> ProcRes {
+    let irfile = output_base_name(config, testfile).with_extension("ll");
+    let prog = config.llvm_bin_path.as_ref().unwrap().join("FileCheck");
     let proc_args = ProcArgs {
         // FIXME (#9639): This needs to handle non-utf8 paths
         prog: prog.to_str().unwrap().to_string(),
-        args: vec!(format!("-func={}", fname),
-                   format!("-o={}", extracted_bc.to_str().unwrap()),
-                   bitcodefile.to_str().unwrap().to_string())
+        args: vec!(format!("-input-file={}", irfile.to_str().unwrap()),
+                   testfile.to_str().unwrap().to_string())
     };
     compose_and_run(config, testfile, proc_args, Vec::new(), "", None, None)
 }
 
-fn disassemble_extract(config: &Config, _props: &TestProps,
-                       testfile: &Path, suffix: &str) -> ProcRes {
-    let bitcodefile = output_base_name(config, testfile).with_extension("bc");
-    let bitcodefile = append_suffix_to_stem(&bitcodefile, suffix);
-    let extracted_bc = append_suffix_to_stem(&bitcodefile, "extract");
-    let extracted_ll = extracted_bc.with_extension("ll");
-    let prog = config.llvm_bin_path.as_ref().unwrap().join("llvm-dis");
-    let proc_args = ProcArgs {
-        // FIXME (#9639): This needs to handle non-utf8 paths
-        prog: prog.to_str().unwrap().to_string(),
-        args: vec!(format!("-o={}", extracted_ll.to_str().unwrap()),
-                   extracted_bc.to_str().unwrap().to_string())
-    };
-    compose_and_run(config, testfile, proc_args, Vec::new(), "", None, None)
-}
-
-
-fn count_extracted_lines(p: &Path) -> usize {
-    let mut x = Vec::new();
-    File::open(&p.with_extension("ll")).unwrap().read_to_end(&mut x).unwrap();
-    let x = str::from_utf8(&x).unwrap();
-    x.lines().count()
-}
-
-
-fn run_codegen_test(config: &Config, props: &TestProps,
-                    testfile: &Path, mm: &mut MetricMap) {
+fn run_codegen_test(config: &Config, props: &TestProps, testfile: &Path) {
 
     if config.llvm_bin_path.is_none() {
         fatal("missing --llvm-bin-path");
     }
 
-    if config.clang_path.is_none() {
-        fatal("missing --clang-path");
-    }
-
-    let mut proc_res = compile_test_and_save_bitcode(config, props, testfile);
-    if !proc_res.status.success() {
-        fatal_proc_rec("compilation failed!", &proc_res);
-    }
-
-    proc_res = extract_function_from_bitcode(config, props, "test", testfile, "");
-    if !proc_res.status.success() {
-        fatal_proc_rec("extracting 'test' function failed",
-                      &proc_res);
-    }
-
-    proc_res = disassemble_extract(config, props, testfile, "");
-    if !proc_res.status.success() {
-        fatal_proc_rec("disassembling extract failed", &proc_res);
-    }
-
-
-    let mut proc_res = compile_cc_with_clang_and_save_bitcode(config, props, testfile);
+    let mut proc_res = compile_test_and_save_ir(config, props, testfile);
     if !proc_res.status.success() {
         fatal_proc_rec("compilation failed!", &proc_res);
     }
 
-    proc_res = extract_function_from_bitcode(config, props, "test", testfile, "clang");
+    proc_res = check_ir_with_filecheck(config, testfile);
     if !proc_res.status.success() {
-        fatal_proc_rec("extracting 'test' function failed",
+        fatal_proc_rec("verification with 'FileCheck' failed",
                       &proc_res);
     }
-
-    proc_res = disassemble_extract(config, props, testfile, "clang");
-    if !proc_res.status.success() {
-        fatal_proc_rec("disassembling extract failed", &proc_res);
-    }
-
-    let base = output_base_name(config, testfile);
-    let base_extract = append_suffix_to_stem(&base, "extract");
-
-    let base_clang = append_suffix_to_stem(&base, "clang");
-    let base_clang_extract = append_suffix_to_stem(&base_clang, "extract");
-
-    let base_lines = count_extracted_lines(&base_extract);
-    let clang_lines = count_extracted_lines(&base_clang_extract);
-
-    mm.insert_metric("clang-codegen-ratio",
-                     (base_lines as f64) / (clang_lines as f64),
-                     0.001);
 }
 
 fn charset() -> &'static str {
diff --git a/src/test/codegen/function-arguments.rs b/src/test/codegen/function-arguments.rs
new file mode 100644
index 00000000000..f11e769ca6c
--- /dev/null
+++ b/src/test/codegen/function-arguments.rs
@@ -0,0 +1,95 @@
+// Copyright 2015 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// compile-flags: -C no-prepopulate-passes
+
+#![feature(allocator)]
+
+pub struct S {
+  _field: [i64; 4],
+}
+
+pub struct UnsafeInner {
+  _field: std::cell::UnsafeCell<i16>,
+}
+
+// CHECK: zeroext i1 @boolean(i1 zeroext)
+#[no_mangle]
+pub fn boolean(x: bool) -> bool {
+  x
+}
+
+// CHECK: @readonly_borrow(i32* noalias readonly dereferenceable(4))
+// FIXME #25759 This should also have `nocapture`
+#[no_mangle]
+pub fn readonly_borrow(_: &i32) {
+}
+
+// CHECK: @static_borrow(i32* noalias readonly dereferenceable(4))
+// static borrow may be captured
+#[no_mangle]
+pub fn static_borrow(_: &'static i32) {
+}
+
+// CHECK: @named_borrow(i32* noalias readonly dereferenceable(4))
+// borrow with named lifetime may be captured
+#[no_mangle]
+pub fn named_borrow<'r>(_: &'r i32) {
+}
+
+// CHECK: @unsafe_borrow(%UnsafeInner* dereferenceable(2))
+// unsafe interior means this isn't actually readonly and there may be aliases ...
+#[no_mangle]
+pub fn unsafe_borrow(_: &UnsafeInner) {
+}
+
+// CHECK: @mutable_unsafe_borrow(%UnsafeInner* noalias dereferenceable(2))
+// ... unless this is a mutable borrow, those never alias
+#[no_mangle]
+pub fn mutable_unsafe_borrow(_: &mut UnsafeInner) {
+}
+
+// CHECK: @mutable_borrow(i32* noalias dereferenceable(4))
+// FIXME #25759 This should also have `nocapture`
+#[no_mangle]
+pub fn mutable_borrow(_: &mut i32) {
+}
+
+// CHECK: @indirect_struct(%S* noalias nocapture dereferenceable(32))
+#[no_mangle]
+pub fn indirect_struct(_: S) {
+}
+
+// CHECK: @borrowed_struct(%S* noalias readonly dereferenceable(32))
+// FIXME #25759 This should also have `nocapture`
+#[no_mangle]
+pub fn borrowed_struct(_: &S) {
+}
+
+// CHECK: noalias dereferenceable(4) i32* @_box(i32* noalias dereferenceable(4))
+#[no_mangle]
+pub fn _box(x: Box<i32>) -> Box<i32> {
+  x
+}
+
+// CHECK: @struct_return(%S* noalias nocapture sret dereferenceable(32))
+#[no_mangle]
+pub fn struct_return() -> S {
+  S {
+    _field: [0, 0, 0, 0]
+  }
+}
+
+// CHECK: noalias i8* @allocator()
+#[no_mangle]
+#[allocator]
+pub fn allocator() -> *const i8 {
+  std::ptr::null()
+}
diff --git a/src/test/codegen/iterate-over-array.cc b/src/test/codegen/iterate-over-array.cc
deleted file mode 100644
index 9261bddb747..00000000000
--- a/src/test/codegen/iterate-over-array.cc
+++ /dev/null
@@ -1,27 +0,0 @@
-// Copyright 2013 The Rust Project Developers. See the COPYRIGHT
-// file at the top-level directory of this distribution and at
-// http://rust-lang.org/COPYRIGHT.
-//
-// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
-// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
-// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
-// option. This file may not be copied, modified, or distributed
-// except according to those terms.
-
-#include <stdlib.h>
-#include <assert.h>
-
-struct slice {
-  int const *p;
-  size_t len;
-};
-
-extern "C"
-size_t test(slice s) {
-  size_t y = 0;
-  for (int i = 0; i < s.len; ++i) {
-	assert(i < s.len);
-	y += s.p[i];
-  }
-  return y;
-}
diff --git a/src/test/codegen/iterate-over-array.rs b/src/test/codegen/iterate-over-array.rs
deleted file mode 100644
index a5b449285ef..00000000000
--- a/src/test/codegen/iterate-over-array.rs
+++ /dev/null
@@ -1,20 +0,0 @@
-// Copyright 2013 The Rust Project Developers. See the COPYRIGHT
-// file at the top-level directory of this distribution and at
-// http://rust-lang.org/COPYRIGHT.
-//
-// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
-// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
-// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
-// option. This file may not be copied, modified, or distributed
-// except according to those terms.
-
-#[no_mangle]
-pub fn test(x: &[isize]) -> isize {
-    let mut y = 0;
-    let mut i = 0;
-    while (i < x.len()) {
-        y += x[i];
-        i += 1;
-    }
-    y
-}
diff --git a/src/test/codegen/loads.rs b/src/test/codegen/loads.rs
new file mode 100644
index 00000000000..20a55740bb7
--- /dev/null
+++ b/src/test/codegen/loads.rs
@@ -0,0 +1,52 @@
+// Copyright 2015 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// compile-flags: -C no-prepopulate-passes
+
+pub struct Bytes {
+  a: u8,
+  b: u8,
+  c: u8,
+  d: u8,
+}
+
+// CHECK-LABEL: @borrow
+#[no_mangle]
+pub fn borrow(x: &i32) -> &i32 {
+// CHECK: load i32** %x{{.*}}, !nonnull
+    x
+}
+
+// CHECK-LABEL: @_box
+#[no_mangle]
+pub fn _box(x: Box<i32>) -> i32 {
+// CHECK: load i32** %x{{.*}}, !nonnull
+    *x
+}
+
+// CHECK-LABEL: small_array_alignment
+// The array is loaded as i32, but its alignment is lower, go with 1 byte to avoid target
+// dependent alignment
+#[no_mangle]
+pub fn small_array_alignment(x: [i8; 4]) -> [i8; 4] {
+// CHECK: [[VAR:%[0-9]+]] = load i32* %{{.*}}, align 1
+// CHECK: ret i32 [[VAR]]
+    x
+}
+
+// CHECK-LABEL: small_struct_alignment
+// The struct is loaded as i32, but its alignment is lower, go with 1 byte to avoid target
+// dependent alignment
+#[no_mangle]
+pub fn small_struct_alignment(x: Bytes) -> Bytes {
+// CHECK: [[VAR:%[0-9]+]] = load i32* %{{.*}}, align 1
+// CHECK: ret i32 [[VAR]]
+    x
+}
diff --git a/src/test/codegen/scalar-function-call.cc b/src/test/codegen/scalar-function-call.cc
deleted file mode 100644
index ce3173ce464..00000000000
--- a/src/test/codegen/scalar-function-call.cc
+++ /dev/null
@@ -1,20 +0,0 @@
-// Copyright 2013 The Rust Project Developers. See the COPYRIGHT
-// file at the top-level directory of this distribution and at
-// http://rust-lang.org/COPYRIGHT.
-//
-// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
-// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
-// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
-// option. This file may not be copied, modified, or distributed
-// except according to those terms.
-
-#include <stdlib.h>
-
-size_t foo(size_t x) {
-    return x * x;
-}
-
-extern "C"
-void test() {
-    size_t x = foo(10);
-}
diff --git a/src/test/codegen/scalar-function-call.rs b/src/test/codegen/scalar-function-call.rs
deleted file mode 100644
index fe93c864fad..00000000000
--- a/src/test/codegen/scalar-function-call.rs
+++ /dev/null
@@ -1,18 +0,0 @@
-// Copyright 2013 The Rust Project Developers. See the COPYRIGHT
-// file at the top-level directory of this distribution and at
-// http://rust-lang.org/COPYRIGHT.
-//
-// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
-// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
-// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
-// option. This file may not be copied, modified, or distributed
-// except according to those terms.
-
-fn foo(x: isize) -> isize {
-    x * x
-}
-
-#[no_mangle]
-pub fn test() {
-    let _x = foo(10);
-}
diff --git a/src/test/codegen/single-return-value.cc b/src/test/codegen/single-return-value.cc
deleted file mode 100644
index 97d80d3950f..00000000000
--- a/src/test/codegen/single-return-value.cc
+++ /dev/null
@@ -1,14 +0,0 @@
-// Copyright 2013 The Rust Project Developers. See the COPYRIGHT
-// file at the top-level directory of this distribution and at
-// http://rust-lang.org/COPYRIGHT.
-//
-// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
-// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
-// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
-// option. This file may not be copied, modified, or distributed
-// except according to those terms.
-
-extern "C"
-int test() {
-  return 5;
-}
diff --git a/src/test/codegen/single-return-value.rs b/src/test/codegen/single-return-value.rs
deleted file mode 100644
index 5addba1724d..00000000000
--- a/src/test/codegen/single-return-value.rs
+++ /dev/null
@@ -1,14 +0,0 @@
-// Copyright 2013 The Rust Project Developers. See the COPYRIGHT
-// file at the top-level directory of this distribution and at
-// http://rust-lang.org/COPYRIGHT.
-//
-// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
-// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
-// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
-// option. This file may not be copied, modified, or distributed
-// except according to those terms.
-
-#[no_mangle]
-pub fn test() -> isize {
-    5
-}
diff --git a/src/test/codegen/small-dense-int-switch.cc b/src/test/codegen/small-dense-int-switch.cc
deleted file mode 100644
index db93829c62b..00000000000
--- a/src/test/codegen/small-dense-int-switch.cc
+++ /dev/null
@@ -1,21 +0,0 @@
-// Copyright 2013 The Rust Project Developers. See the COPYRIGHT
-// file at the top-level directory of this distribution and at
-// http://rust-lang.org/COPYRIGHT.
-//
-// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
-// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
-// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
-// option. This file may not be copied, modified, or distributed
-// except according to those terms.
-
-#include <stdlib.h>
-
-extern "C"
-size_t test(size_t x, size_t y) {
-  switch (x) {
-  case 1: return y;
-  case 2: return y*2;
-  case 4: return y*3;
-  default: return 11;
-  }
-}
diff --git a/src/test/codegen/small-dense-int-switch.rs b/src/test/codegen/small-dense-int-switch.rs
deleted file mode 100644
index cf05a2e2f8e..00000000000
--- a/src/test/codegen/small-dense-int-switch.rs
+++ /dev/null
@@ -1,19 +0,0 @@
-// Copyright 2013 The Rust Project Developers. See the COPYRIGHT
-// file at the top-level directory of this distribution and at
-// http://rust-lang.org/COPYRIGHT.
-//
-// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
-// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
-// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
-// option. This file may not be copied, modified, or distributed
-// except according to those terms.
-
-#[no_mangle]
-pub fn test(x: isize, y: isize) -> isize {
-    match x {
-        1 => y,
-        2 => y*2,
-        4 => y*3,
-        _ => 11
-    }
-}
diff --git a/src/test/codegen/stack-alloc-string-slice.cc b/src/test/codegen/stack-alloc-string-slice.cc
deleted file mode 100644
index a81f76eee0b..00000000000
--- a/src/test/codegen/stack-alloc-string-slice.cc
+++ /dev/null
@@ -1,22 +0,0 @@
-// Copyright 2013 The Rust Project Developers. See the COPYRIGHT
-// file at the top-level directory of this distribution and at
-// http://rust-lang.org/COPYRIGHT.
-//
-// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
-// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
-// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
-// option. This file may not be copied, modified, or distributed
-// except according to those terms.
-
-#include <stddef.h>
-
-struct slice {
-  char const *p;
-  size_t len;
-};
-
-extern "C"
-void test() {
-  struct slice s = { .p = "hello",
-                     .len = 5 };
-}
diff --git a/src/test/codegen/stack-alloc-string-slice.rs b/src/test/codegen/stack-alloc-string-slice.rs
deleted file mode 100644
index 188ee246bf3..00000000000
--- a/src/test/codegen/stack-alloc-string-slice.rs
+++ /dev/null
@@ -1,14 +0,0 @@
-// Copyright 2013 The Rust Project Developers. See the COPYRIGHT
-// file at the top-level directory of this distribution and at
-// http://rust-lang.org/COPYRIGHT.
-//
-// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
-// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
-// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
-// option. This file may not be copied, modified, or distributed
-// except according to those terms.
-
-#[no_mangle]
-pub fn test() {
-    let _x = "hello";
-}
diff --git a/src/test/codegen/static-method-call-multi.cc b/src/test/codegen/static-method-call-multi.cc
deleted file mode 100644
index 6c03e32b98c..00000000000
--- a/src/test/codegen/static-method-call-multi.cc
+++ /dev/null
@@ -1,27 +0,0 @@
-// Copyright 2013 The Rust Project Developers. See the COPYRIGHT
-// file at the top-level directory of this distribution and at
-// http://rust-lang.org/COPYRIGHT.
-//
-// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
-// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
-// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
-// option. This file may not be copied, modified, or distributed
-// except according to those terms.
-
-#include <stdlib.h>
-
-struct Struct {
-  size_t field;
-  size_t method(size_t x) {
-	return this->field + x;
-  }
-};
-
-extern "C"
-size_t test(Struct &a,
-			Struct &b,
-			Struct &c,
-			Struct &d,
-			Struct &e) {
-  return a.method(b.method(c.method(d.method(e.method(1)))));
-}
diff --git a/src/test/codegen/static-method-call-multi.rs b/src/test/codegen/static-method-call-multi.rs
deleted file mode 100644
index 025f9b524c9..00000000000
--- a/src/test/codegen/static-method-call-multi.rs
+++ /dev/null
@@ -1,28 +0,0 @@
-// Copyright 2013 The Rust Project Developers. See the COPYRIGHT
-// file at the top-level directory of this distribution and at
-// http://rust-lang.org/COPYRIGHT.
-//
-// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
-// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
-// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
-// option. This file may not be copied, modified, or distributed
-// except according to those terms.
-
-pub struct Struct {
-    field: isize
-}
-
-impl Struct {
-    fn method(&self, x: isize) -> isize {
-        self.field + x
-    }
-}
-
-#[no_mangle]
-pub fn test(a: &Struct,
-            b: &Struct,
-            c: &Struct,
-            d: &Struct,
-            e: &Struct) -> isize {
-    a.method(b.method(c.method(d.method(e.method(1)))))
-}
diff --git a/src/test/codegen/static-method-call.cc b/src/test/codegen/static-method-call.cc
deleted file mode 100644
index 36cfa4f4d84..00000000000
--- a/src/test/codegen/static-method-call.cc
+++ /dev/null
@@ -1,23 +0,0 @@
-// Copyright 2013 The Rust Project Developers. See the COPYRIGHT
-// file at the top-level directory of this distribution and at
-// http://rust-lang.org/COPYRIGHT.
-//
-// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
-// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
-// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
-// option. This file may not be copied, modified, or distributed
-// except according to those terms.
-
-#include <stdlib.h>
-
-struct Struct {
-  size_t field;
-  size_t method() {
-	return this->field;
-  }
-};
-
-extern "C"
-size_t test(Struct &s) {
-  return s.method();
-}
diff --git a/src/test/codegen/static-method-call.rs b/src/test/codegen/static-method-call.rs
deleted file mode 100644
index fca3784d9e0..00000000000
--- a/src/test/codegen/static-method-call.rs
+++ /dev/null
@@ -1,24 +0,0 @@
-// Copyright 2013 The Rust Project Developers. See the COPYRIGHT
-// file at the top-level directory of this distribution and at
-// http://rust-lang.org/COPYRIGHT.
-//
-// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
-// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
-// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
-// option. This file may not be copied, modified, or distributed
-// except according to those terms.
-
-pub struct Struct {
-    field: isize
-}
-
-impl Struct {
-    fn method(&self) -> isize {
-        self.field
-    }
-}
-
-#[no_mangle]
-pub fn test(s: &Struct) -> isize {
-    s.method()
-}
diff --git a/src/test/codegen/stores.rs b/src/test/codegen/stores.rs
new file mode 100644
index 00000000000..32337b085cd
--- /dev/null
+++ b/src/test/codegen/stores.rs
@@ -0,0 +1,45 @@
+// Copyright 2015 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// compile-flags: -C no-prepopulate-passes
+
+pub struct Bytes {
+  a: u8,
+  b: u8,
+  c: u8,
+  d: u8,
+}
+
+// CHECK-LABEL: small_array_alignment
+// The array is stored as i32, but its alignment is lower, go with 1 byte to avoid target
+// dependent alignment
+#[no_mangle]
+pub fn small_array_alignment(x: &mut [i8; 4]) {
+// CHECK: [[VAR:%[0-9]+]] = load [4 x i8]** %x
+// CHECK: [[VAR2:%[0-9]+]] = bitcast [4 x i8]* [[VAR]] to i32*
+// CHECK: store i32 %{{.*}}, i32* [[VAR2]], align 1
+    *x = [0; 4];
+}
+
+// CHECK-LABEL: small_struct_alignment
+// The struct is stored as i32, but its alignment is lower, go with 1 byte to avoid target
+// dependent alignment
+#[no_mangle]
+pub fn small_struct_alignment(x: &mut Bytes) {
+// CHECK: [[VAR:%[0-9]+]] = load %Bytes** %x
+// CHECK: [[VAR2:%[0-9]+]] = bitcast %Bytes* [[VAR]] to i32*
+// CHECK: store i32 %{{.*}}, i32* [[VAR2]], align 1
+    *x = Bytes {
+        a: 0,
+        b: 0,
+        c: 0,
+        d: 0,
+    };
+}
diff --git a/src/test/codegen/virtual-method-call-struct-return.cc b/src/test/codegen/virtual-method-call-struct-return.cc
deleted file mode 100644
index 345f21c5647..00000000000
--- a/src/test/codegen/virtual-method-call-struct-return.cc
+++ /dev/null
@@ -1,25 +0,0 @@
-// Copyright 2013 The Rust Project Developers. See the COPYRIGHT
-// file at the top-level directory of this distribution and at
-// http://rust-lang.org/COPYRIGHT.
-//
-// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
-// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
-// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
-// option. This file may not be copied, modified, or distributed
-// except according to those terms.
-
-#include <stdlib.h>
-
-struct Stuff {
-  size_t a;
-  double b;
-};
-
-struct Struct {
-  virtual Stuff method() = 0;
-};
-
-extern "C"
-size_t test(Struct &s) {
-  return s.method().a;
-}
diff --git a/src/test/codegen/virtual-method-call-struct-return.rs b/src/test/codegen/virtual-method-call-struct-return.rs
deleted file mode 100644
index ae83409b45f..00000000000
--- a/src/test/codegen/virtual-method-call-struct-return.rs
+++ /dev/null
@@ -1,23 +0,0 @@
-// Copyright 2013 The Rust Project Developers. See the COPYRIGHT
-// file at the top-level directory of this distribution and at
-// http://rust-lang.org/COPYRIGHT.
-//
-// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
-// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
-// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
-// option. This file may not be copied, modified, or distributed
-// except according to those terms.
-
-pub struct Stuff {
-  a: isize,
-  b: f64
-}
-
-pub trait Trait {
-    fn method(&self) -> Stuff;
-}
-
-#[no_mangle]
-pub fn test(t: &Trait) -> isize {
-    t.method().a
-}
diff --git a/src/test/codegen/virtual-method-call.cc b/src/test/codegen/virtual-method-call.cc
deleted file mode 100644
index 9fcafdf6594..00000000000
--- a/src/test/codegen/virtual-method-call.cc
+++ /dev/null
@@ -1,20 +0,0 @@
-// Copyright 2013 The Rust Project Developers. See the COPYRIGHT
-// file at the top-level directory of this distribution and at
-// http://rust-lang.org/COPYRIGHT.
-//
-// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
-// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
-// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
-// option. This file may not be copied, modified, or distributed
-// except according to those terms.
-
-#include <stdlib.h>
-
-struct Struct {
-  virtual size_t method() = 0;
-};
-
-extern "C"
-size_t test(Struct &s) {
-  return s.method();
-}
diff --git a/src/test/codegen/virtual-method-call.rs b/src/test/codegen/virtual-method-call.rs
deleted file mode 100644
index 9bfeef1f018..00000000000
--- a/src/test/codegen/virtual-method-call.rs
+++ /dev/null
@@ -1,18 +0,0 @@
-// Copyright 2013 The Rust Project Developers. See the COPYRIGHT
-// file at the top-level directory of this distribution and at
-// http://rust-lang.org/COPYRIGHT.
-//
-// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
-// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
-// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
-// option. This file may not be copied, modified, or distributed
-// except according to those terms.
-
-pub trait Trait {
-    fn method(&self) -> isize;
-}
-
-#[no_mangle]
-pub fn test(t: &Trait) -> isize {
-    t.method()
-}