mlugg 407dc6eee4

Liveness: avoid emitting unused instructions or marking their operands as used ...

Backends want to avoid emitting unused instructions which do not have
side effects: to that end, they all have `Liveness.isUnused` checks for
many instructions. However, checking this in the backends avoids a lot
of potential optimizations. For instance, if a nested field is loaded,
then the first field access would still be emitted, since its result is
used by the next access (which is then unreferenced).

To elide more instructions, Liveness can track this data instead. For
operands which do not have to be lowered (i.e. are not side effecting
and are not something special like `arg), Liveness can ignore their
operand usages, and push the unused information further up, potentially
marking many more instructions as unreferenced.

In doing this, I also uncovered a bug in the LLVM backend relating to
discarding the result of `@cVaArg`, which this change fixes. A behaviour
test has been added to cover it.

2023-04-20 20:28:48 +01:00

..

bugs

behavior: disable flaky test on x86_64

2023-04-16 17:07:07 -04:00

hasdecl

move behavior tests from test/stage1/ to test/

2021-04-29 15:54:04 -07:00

import

move behavior tests from test/stage1/ to test/

2021-04-29 15:54:04 -07:00

namespace_depends_on_compile_var

move behavior tests from test/stage1/ to test/

2021-04-29 15:54:04 -07:00

pub_enum

move behavior tests from test/stage1/ to test/

2021-04-29 15:54:04 -07:00

usingnamespace

stage2: sparc64: Skip unimplemented tests

2022-12-10 21:51:46 +07:00

align.zig

x86_64: implement large cmp

2023-04-02 04:49:53 -04:00

alignof.zig

stage2 AArch64: unify callee-preserved regs on all targets

2022-12-27 21:17:52 +08:00

array.zig

Sema: allow ptr field access on pointer-to-array

2023-04-20 09:05:22 -07:00

asm.zig

CBE: fix windows test failures

2023-02-21 15:46:34 -05:00

async_fn.zig

remove references to stage1 in behavior tests

2022-12-06 19:06:48 -07:00

atomics.zig

CI: more C backend test coverage

2023-04-15 10:33:08 -07:00

await_struct.zig

remove references to stage1 in behavior tests

2022-12-06 19:06:48 -07:00

basic.zig

x86_64: implement large cmp

2023-04-02 04:49:53 -04:00

bit_shifting.zig

behavior: enable passing behavior tests on stage2_x86_64

2023-03-15 01:04:21 -04:00

bitcast.zig

x86_64: implement large cmp

2023-04-02 04:49:53 -04:00

bitreverse.zig

behavior: enable passing behavior tests on stage2_x86_64

2023-03-15 01:04:21 -04:00

bool.zig

C backend: fix @boolToInt

2021-10-28 17:33:05 -07:00

builtin_functions_returning_void_or_noreturn.zig

x86_64: implement large cmp

2023-04-02 04:49:53 -04:00

byteswap.zig

behavior: enable passing behavior tests on stage2_x86_64

2023-03-15 01:04:21 -04:00

byval_arg_var.zig

behavior: enable passing behavior tests on stage2_x86_64

2023-03-15 01:04:21 -04:00

call.zig

x86_64: (re)implement optional ops

2023-03-21 08:49:54 +01:00

cast_int.zig

x86_64: implement large cmp

2023-04-02 04:49:53 -04:00

cast.zig

disable more failing C backend tests

2023-04-15 10:33:08 -07:00

comptime_memory.zig

Sema: allow dereferencing ill-defined pointers to zero-bit types at comptime

2023-03-17 01:56:36 -04:00

const_slice_child.zig

Liveness: defer deaths of externally-scoped instructions in loop bodies

2023-04-07 01:29:20 +01:00

decltest.zig

stage2: add decltests

2022-02-13 14:42:20 +02:00

defer.zig

x86_64: implement error name

2023-04-02 04:49:53 -04:00

empty_file_level_struct.zig

fix overflow found while fuzzing

2022-12-23 23:10:04 +02:00

empty_file_level_union.zig

fix overflow found while fuzzing

2022-12-23 23:10:04 +02:00

empty_tuple_fields.zig

x86_64: implement atomic loops

2023-03-25 16:23:55 -04:00

empty_union.zig

stage2: fix onePossibleValue of empty unions and enums

2022-11-04 23:13:50 +02:00

enum.zig

x86_64: implement packed load and store

2023-04-16 17:05:35 -04:00

error.zig

x86_64: fix typos

2023-04-03 18:02:55 +02:00

eval.zig

Zir: implement explicit block_comptime instruction

2023-04-12 12:06:19 -04:00

export_self_referential_type_info.zig

behavior: fix redefined exports

2022-10-25 05:11:28 -04:00

export.zig

Sema: implement @export for arbitrary values

2023-03-21 15:04:39 +02:00

field_parent_ptr.zig

arm: skip unimplemented behavior test for @fieldParentPtr

2023-03-03 18:42:29 +01:00

floatop.zig

disable more failing C backend tests

2023-04-15 10:33:08 -07:00

fn_delegation.zig

stage2: sparc64: Skip unimplemented tests

2022-12-10 21:51:46 +07:00

fn_in_struct_in_comptime.zig

Merge remote-tracking branch 'origin/master' into stage2-whole-file-astgen

2021-05-08 14:45:21 -07:00

fn.zig

x86_64: implement struct_field_ptr for packed containers

2023-03-25 16:23:55 -04:00

for.zig

Liveness: defer deaths of externally-scoped instructions in loop bodies

2023-04-07 01:29:20 +01:00

generics.zig

behavior: enable passing behavior tests on stage2_x86_64

2023-03-15 01:04:21 -04:00

hasdecl.zig

Merge remote-tracking branch 'origin/master' into stage2-whole-file-astgen

2021-05-08 14:45:21 -07:00

hasfield.zig

Sema: make @hasField support tuples too

2022-03-11 12:59:20 -07:00

if.zig

Sema: defer stores to inferred allocs

2023-04-02 18:05:44 +03:00

import.zig

lint: duplicate import (#10519)

2022-01-07 00:06:06 -05:00

incomplete_struct_param_tld.zig

stage2: sparc64: Skip unimplemented tests

2022-12-10 21:51:46 +07:00

inline_switch.zig

x86_64: handle duplicate prong deaths

2023-03-15 01:04:21 -04:00

int128.zig

x86_64: implement large add/sub with overflow

2023-04-02 05:16:46 -04:00

int_comparison_elision.zig

behavior: enable passing CBE tests

2023-02-21 09:43:23 -05:00

int_div.zig

x86_64: implement large cmp

2023-04-02 04:49:53 -04:00

inttoptr.zig

x86_64: implement store to immediate address

2023-04-03 17:45:16 +02:00

ir_block_deps.zig

stage2: sparc64: Skip unimplemented tests

2022-12-10 21:51:46 +07:00

lower_strlit_to_vector.zig

x86_64: implement atomic loops

2023-03-25 16:23:55 -04:00

math.zig

disable more failing C backend tests

2023-04-15 10:33:08 -07:00

maximum_minimum.zig

x86_64: implement basic float ops

2023-03-21 08:49:54 +01:00

member_func.zig

behavior: enable passing behavior tests on stage2_x86_64

2023-03-15 01:04:21 -04:00

merge_error_sets.zig

x86_64: implement atomic and fence ops

2023-03-21 08:49:54 +01:00

muladd.zig

disable more failing C backend tests

2023-04-15 10:33:08 -07:00

namespace_depends_on_compile_var.zig

CBE: enable more tests that are currently passing

2022-03-17 11:39:56 -07:00

null.zig

x86_64: (re)implement optional ops

2023-03-21 08:49:54 +01:00

optional.zig

x86_64: implement large cmp

2023-04-02 04:49:53 -04:00

packed_struct_explicit_backing_int.zig

x86_64: implement atomic loops

2023-03-25 16:23:55 -04:00

packed-struct.zig

x86_64: implement aggregate init of a packed struct

2023-04-02 04:49:53 -04:00

pointers.zig

x86_64: fix constant pointers to zero-bit types

2023-04-13 04:17:47 -04:00

popcount.zig

CBE: implement some big integer and vector unary operations

2023-03-05 02:59:01 -05:00

prefetch.zig

stage1: implement @prefetch() builtin

2021-12-11 00:29:31 +01:00

ptrcast.zig

x86_64: (re)implement optional ops

2023-03-21 08:49:54 +01:00

pub_enum.zig

Merge remote-tracking branch 'origin/master' into stage2-whole-file-astgen

2021-05-08 14:45:21 -07:00

ref_var_in_if_after_if_2nd_switch_prong.zig

behavior: enable passing behavior tests on stage2_x86_64

2023-03-15 01:04:21 -04:00

reflection.zig

behavior: enable passing behavior tests on stage2_x86_64

2023-03-15 01:04:21 -04:00

return_address.zig

x86_64: implement @returnAddress and @frameAddress

2023-03-21 08:49:54 +01:00

saturating_arithmetic.zig

stage2: sparc64: Skip unimplemented tests

2022-12-10 21:51:46 +07:00

select.zig

CBE: implement select and shuffle

2023-03-05 02:59:02 -05:00

shuffle.zig

Enable new tests

2023-04-07 20:55:04 -04:00

sizeof_and_typeof.zig

behavior: enable passing behavior tests on stage2_x86_64

2023-03-15 01:04:21 -04:00

slice_sentinel_comptime.zig

std, src, doc, test: remove unused variables

2021-06-21 17:03:03 -07:00

slice.zig

Liveness: defer deaths of externally-scoped instructions in loop bodies

2023-04-07 01:29:20 +01:00

src.zig

Value: handle comparisons of runtime_values

2023-03-21 00:34:12 +02:00

struct_contains_null_ptr_itself.zig

behavior: enable passing behavior tests on stage2_x86_64

2023-03-15 01:04:21 -04:00

struct_contains_slice_of_itself.zig

stage2 AArch64: unify callee-preserved regs on all targets

2022-12-27 21:17:52 +08:00

struct.zig

x86_64: implement packed load and store

2023-04-16 17:05:35 -04:00

switch_prong_err_enum.zig

x86_64: fix typos

2023-04-03 18:02:55 +02:00

switch_prong_implicit_cast.zig

x86_64: fix typos

2023-04-03 18:02:55 +02:00

switch.zig

Sema: implement inline switch capture at comptime

2023-04-05 14:45:56 +03:00

this.zig

stage2: sparc64: Skip unimplemented tests

2022-12-10 21:51:46 +07:00

threadlocal.zig

x86_64: implement atomic loops

2023-03-25 16:23:55 -04:00

translate_c_macros_not_utf8.h

translate-c: Escape non-ASCII characters that appear in macros

2022-09-10 01:50:17 +03:00

translate_c_macros.h

Translate-C Remainder Macro Fix

2022-11-03 14:07:00 +02:00

translate_c_macros.zig

x86_64: implement atomic loops

2023-03-25 16:23:55 -04:00

truncate.zig

CBE: implement vector truncate

2023-03-05 02:59:02 -05:00

try.zig

stage2 AArch64: implement errUnion{Err,Payload} for registers

2022-12-29 11:12:08 +01:00

tuple_declarations.zig

x86_64: implement atomic loops

2023-03-25 16:23:55 -04:00

tuple.zig

x86_64: implement atomic loops

2023-03-25 16:23:55 -04:00

type_info.zig

x86_64: implement atomic loops

2023-03-25 16:23:55 -04:00

type.zig

x86_64: implement atomic loops

2023-03-25 16:23:55 -04:00

typename.zig

x86_64: implement large cmp

2023-04-02 04:49:53 -04:00

undefined.zig

stage2 AArch64: unify callee-preserved regs on all targets

2022-12-27 21:17:52 +08:00

underscore.zig

stage2 AArch64: unify callee-preserved regs on all targets

2022-12-27 21:17:52 +08:00

union_with_members.zig

x86_64: handle duplicate prong deaths

2023-03-15 01:04:21 -04:00

union.zig

Sema: defer stores to inferred allocs

2023-04-02 18:05:44 +03:00

usingnamespace.zig

stage2: sparc64: Skip unimplemented tests

2022-12-10 21:51:46 +07:00

var_args.zig

Liveness: avoid emitting unused instructions or marking their operands as used

2023-04-20 20:28:48 +01:00

vector.zig

disable more failing C backend tests

2023-04-15 10:33:08 -07:00

void.zig

behavior: enable passing behavior tests on stage2_x86_64

2023-03-15 01:04:21 -04:00

wasm.zig

stage2: cleanups to wasm memory intrinsics

2022-03-03 18:31:55 -07:00

while.zig

x86_64: (re)implement optional ops

2023-03-21 08:49:54 +01:00

widening.zig

disable more failing C backend tests

2023-04-15 10:33:08 -07:00

wrapping_arithmetic.zig

stage1: fix saturating arithmetic producing incorrect results on type comptime_int, allow saturating left shift on type comptime int

2022-01-29 18:12:28 +02:00