rust/tests/codegen
..
auxiliary
avr
cffi
cross-crate-inlining
debug-accessibility
dllimports
enum
float
instrument-coverage
instrument-xray
intrinsics
issues
lib-optimizations
loongarch-abi
macos
meta-filecheck
naked-fn
non-terminate
remap_path_prefix
repr
riscv-abi
sanitizer
simd
simd-intrinsic
src-hash-algorithm
unwind-abis
aarch64-struct-align-128.rs
abi-efiapi.rs
abi-main-signature-16bit-c-int.rs
abi-main-signature-32bit-c-int.rs
abi-repr-ext.rs
abi-sysv64.rs
abi-x86-interrupt.rs
abi-x86_64_sysv.rs
addr-of-mutate.rs
adjustments.rs
align-byval-alignment-mismatch.rs
align-byval-vector.rs
align-byval.rs
align-enum.rs
align-fn.rs
align-offset.rs
align-struct.rs
alloc-optimisation.rs
array-clone.rs
array-cmp.rs
array-codegen.rs
array-equality.rs
array-map.rs
array-optimized.rs
ascii-char.rs
asm-clobber_abi.rs
asm-clobbers.rs
asm-goto.rs
asm-may_unwind.rs
asm-maybe-uninit.rs
asm-multiple-options.rs
asm-options.rs
asm-powerpc-clobbers.rs
asm-sanitize-llvm.rs
asm-target-clobbers.rs
async-closure-debug.rs
async-fn-debug-awaitee-field.rs
async-fn-debug-msvc.rs
async-fn-debug.rs
atomic-operations.rs
atomicptr.rs
autovectorize-f32x4.rs
binary-search-index-no-bound-check.rs
bool-cmp.rs
box-uninit-bytes.rs
bpf-alu32.rs
branch-protection.rs
call-llvm-intrinsics.rs
call-metadata.rs
cast-target-abi.rs
catch-unwind.rs
cdylib-external-inline-fns.rs
cf-protection.rs
cfguard-checks.rs
cfguard-disabled.rs
cfguard-nochecks.rs
cfguard-non-msvc.rs
char-ascii-branchless.rs
checked_ilog.rs
checked_math.rs
codemodels.rs
coercions.rs
cold-call-declare-and-call.rs
common_prim_int_ptr.rs
comparison-operators-2-tuple.rs
comparison-operators-newtype.rs
const_scalar_pair.rs
constant-branch.rs
consts.rs
coroutine-debug-msvc.rs
coroutine-debug.rs
dealloc-no-unwind.rs
debug-alignment.rs
debug-column-msvc.rs
debug-column.rs
debug-compile-unit-path.rs
debug-fndef-size.rs
debug-limited.rs
debug-line-directives-only.rs
debug-line-tables-only.rs
debug-linkage-name.rs
debug-vtable.rs
debuginfo-constant-locals.rs
debuginfo-generic-closure-env-names.rs
debuginfo-inline-callsite-location.rs
deduced-param-attrs.rs
default-hidden-visibility.rs
default-requires-uwtable.rs
direct-access-external-data.rs
dont_codegen_private_const_fn_only_used_in_const_eval.rs
drop-in-place-noalias.rs
drop.rs
dst-offset.rs
dst-vtable-align-nonzero.rs
dst-vtable-size-range.rs
ehcontguard_disabled.rs
ehcontguard_enabled.rs
emcripten-catch-unwind.rs
enable-lto-unit-splitting.rs
export-no-mangle.rs
external-no-mangle-fns.rs
external-no-mangle-statics.rs
fastcall-inreg.rs
fatptr.rs
fewer-names.rs
fixed-x18.rs
float_math.rs
fn-impl-trait-self.rs
foo.s
force-frame-pointers.rs
force-no-unwind-tables.rs
force-unwind-tables.rs
frame-pointer.rs
function-arguments-noopt.rs
function-arguments.rs
function-return.rs
gdb_debug_script_load.rs
generic-debug.rs
global_asm.rs
global_asm_include.rs
global_asm_x2.rs
i128-x86-align.rs
infallible-unwrap-in-opt-z.rs
inherit_overflow.rs
inline-always-works-always.rs
inline-debuginfo.rs
inline-function-args-debug-info.rs
inline-hint.rs
instrument-mcount.rs
integer-cmp.rs
integer-overflow.rs
internalize-closures.rs
intrinsic-no-unnamed-attr.rs
is_val_statically_known.rs
issue-97217.rs
iter-repeat-n-trivial-drop.rs
layout-size-checks.rs
lifetime_start_end.rs
link-dead-code.rs
link_section.rs
llvm-ident.rs
llvm_module_flags.rs
loads.rs
local-generics-in-exe-internalized.rs
lto-removes-invokes.rs
mainsubprogram.rs
mainsubprogramstart.rs
match-optimized.rs
match-optimizes-away.rs
match-unoptimized.rs
maybeuninit-rvo.rs
mem-replace-big-type.rs
mem-replace-simple-type.rs
merge-functions.rs
method-declaration.rs
mir-aggregate-no-alloca.rs
mir-inlined-line-numbers.rs
mir_zst_stores.rs
move-before-nocapture-ref-arg.rs
move-operands.rs
no-assumes-on-casts.rs
no-dllimport-w-cross-lang-lto.rs
no-jump-tables.rs
no-plt.rs
no-redundant-item-monomorphization.rs
no_builtins-at-crate.rs
noalias-box-off.rs
noalias-box.rs
noalias-flag.rs
noalias-freeze.rs
noalias-refcell.rs
noalias-rwlockreadguard.rs
noalias-unpin.rs
noreturn-uninhabited.rs
noreturnflag.rs
nounwind.rs
nrvo.rs
optimize-attr-1.rs
option-as-slice.rs
option-niche-eq.rs
overaligned-constant.rs
packed.rs
panic-abort-windows.rs
panic-in-drop-abort.rs
panic-unwind-default-uwtable.rs
pattern_type_symbols.rs
personality_lifetimes.rs
pgo-counter-bias.rs
pgo-instrumentation.rs
pic-relocation-model.rs
pie-relocation-model.rs
powerpc64le-struct-align-128.rs
precondition-checks.rs
ptr-arithmetic.rs
ptr-read-metadata.rs
README.md
refs.rs
repeat-trusted-len.rs
riscv-target-abi.rs
scalar-pair-bool.rs
set-discriminant-invalid.rs
skip-mono-inside-if-false.rs
slice-as_chunks.rs
slice-indexing.rs
slice-init.rs
slice-iter-fold.rs
slice-iter-len-eq-zero.rs
slice-iter-nonnull.rs
slice-position-bounds-check.rs
slice-ref-equality.rs
slice-reverse.rs
slice-windows-no-bounds-check.rs
slice_as_from_ptr_range.rs
some-abis-do-extend-params-to-32-bits.rs
some-global-nonnull.rs
sparc-struct-abi.rs
split-lto-unit.rs
sroa-fragment-debuginfo.rs
sse42-implies-crc32.rs
stack-probes-inline.rs
stack-protector.rs
static-relocation-model-msvc.rs
staticlib-external-inline-fns.rs
step_by-overflow-checks.rs
stores.rs
swap-large-types.rs
swap-small-types.rs
target-cpu-on-functions.rs
target-feature-inline-closure.rs
target-feature-overrides.rs
thin-lto.rs
thread-local.rs
tied-features-strength.rs
to_vec.rs
trailing_zeros.rs
transmute-optimized.rs
transmute-scalar.rs
try_identity.rs
try_question_mark_nop.rs
tune-cpu-on-functions.rs
tuple-layout-opt.rs
ub-checks.rs
unchecked-float-casts.rs
unchecked_shifts.rs
uninit-consts.rs
union-abi.rs
unwind-and-panic-abort.rs
unwind-extern-exports.rs
unwind-extern-imports.rs
unwind-landingpad-cold.rs
unwind-landingpad-inline.rs
used_with_arg.rs
var-names.rs
vec-as-ptr.rs
vec-calloc.rs
vec-in-place.rs
vec-iter-collect-len.rs
vec-iter.rs
vec-len-invariant.rs
vec-optimizes-away.rs
vec-reserve-extend.rs
vec-shrink-panik.rs
vec-with-capacity.rs
vec_pop_push_noop.rs
vecdeque-drain.rs
vecdeque-nonempty-get-no-panic.rs
vecdeque_no_panic.rs
vecdeque_pop_push.rs
virtual-function-elimination-32bit.rs
virtual-function-elimination.rs
vtable-loads.rs
vtable-upcast.rs
wasm_casts_trapping.rs
wasm_exceptions.rs
zip.rs
zst-offset.rs

The files here use the LLVM FileCheck framework, documented at https://llvm.org/docs/CommandGuide/FileCheck.html.

One extension worth noting is the use of revisions as custom prefixes for FileCheck. If your codegen test has different behavior based on the chosen target or different compiler flags that you want to exercise, you can use a revisions annotation, like so:

// revisions: aaa bbb
// [bbb] compile-flags: --flags-for-bbb

After specifying those variations, you can write different expected, or explicitly unexpected output by using <prefix>-SAME: and <prefix>-NOT:, like so:

// CHECK: expected code
// aaa-SAME: emitted-only-for-aaa
// aaa-NOT:                        emitted-only-for-bbb
// bbb-NOT:  emitted-only-for-aaa
// bbb-SAME:                       emitted-only-for-bbb