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Rollup merge of #96215 - nikic:legacy-pm-removal, r=nagisa

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Drop support for legacy PM with LLVM 15

LLVM 15 already removes some of the legacy PM APIs we're using. This patch forces use of NewPM with LLVM 15 (with `-Z new-llvm-pass-manager=no` throwing a warning) and stubs out various FFI methods with a report_fatal_error on LLVM 15.

For LLVMPassManagerBuilderPopulateLTOPassManager() I went with adding our own wrapper, as the alternative would be to muck about with weak symbols, which seems to be non-trivial as far as cross-platform support is concerned (std has `weak!` for this purpose, but only as an internal utility.)

Fixes #96072.
Fixes #96362.
This commit is contained in:
Matthias Krüger 2022-04-25 00:11:02 +02:00 • committed by GitHub
commit 433f1f425e
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7 changed files with 131 additions and 32 deletions
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2
compiler/rustc_codegen_llvm/src/back/lto.rs
View file

@ -625,7 +625,7 @@ pub(crate) fn run_pass_manager(
if thin {
llvm::LLVMRustPassManagerBuilderPopulateThinLTOPassManager(b, pm);
} else {
llvm::LLVMPassManagerBuilderPopulateLTOPassManager(
llvm::LLVMRustPassManagerBuilderPopulateLTOPassManager(
b, pm, /* Internalize = */ False, /* RunInliner = */ True,
);
}

31
compiler/rustc_codegen_llvm/src/back/write.rs
View file

@ -523,6 +523,12 @@ pub(crate) unsafe fn optimize(
let module_name = module.name.clone();
let module_name = Some(&module_name[..]);
if let Some(false) = config.new_llvm_pass_manager && llvm_util::get_version() >= (15, 0, 0) {
diag_handler.warn(
"ignoring `-Z new-llvm-pass-manager=no`, which is no longer supported with LLVM 15",
);
}
if config.emit_no_opt_bc {
let out = cgcx.output_filenames.temp_path_ext("no-opt.bc", module_name);
let out = path_to_c_string(&out);
@ -628,8 +634,8 @@ pub(crate) unsafe fn optimize(
extra_passes.as_ptr(),
extra_passes.len() as size_t,
);
llvm::LLVMPassManagerBuilderPopulateFunctionPassManager(b, fpm);
llvm::LLVMPassManagerBuilderPopulateModulePassManager(b, mpm);
llvm::LLVMRustPassManagerBuilderPopulateFunctionPassManager(b, fpm);
llvm::LLVMRustPassManagerBuilderPopulateModulePassManager(b, mpm);
});
have_name_anon_globals_pass = have_name_anon_globals_pass || prepare_for_thin_lto;
@ -1085,7 +1091,7 @@ pub unsafe fn with_llvm_pmb(
// Create the PassManagerBuilder for LLVM. We configure it with
// reasonable defaults and prepare it to actually populate the pass
// manager.
let builder = llvm::LLVMPassManagerBuilderCreate();
let builder = llvm::LLVMRustPassManagerBuilderCreate();
let opt_size = config.opt_size.map_or(llvm::CodeGenOptSizeNone, |x| to_llvm_opt_settings(x).1);
let inline_threshold = config.inline_threshold;
let pgo_gen_path = get_pgo_gen_path(config);
@ -1102,14 +1108,9 @@ pub unsafe fn with_llvm_pmb(
pgo_gen_path.as_ref().map_or(ptr::null(), |s| s.as_ptr()),
pgo_use_path.as_ref().map_or(ptr::null(), |s| s.as_ptr()),
pgo_sample_use_path.as_ref().map_or(ptr::null(), |s| s.as_ptr()),
opt_size as c_int,
);
llvm::LLVMPassManagerBuilderSetSizeLevel(builder, opt_size as u32);
if opt_size != llvm::CodeGenOptSizeNone {
llvm::LLVMPassManagerBuilderSetDisableUnrollLoops(builder, 1);
}
llvm::LLVMRustAddBuilderLibraryInfo(builder, llmod, config.no_builtins);
// Here we match what clang does (kinda). For O0 we only inline
@ -1118,16 +1119,16 @@ pub unsafe fn with_llvm_pmb(
// thresholds copied from clang.
match (opt_level, opt_size, inline_threshold) {
(.., Some(t)) => {
llvm::LLVMPassManagerBuilderUseInlinerWithThreshold(builder, t);
llvm::LLVMRustPassManagerBuilderUseInlinerWithThreshold(builder, t);
}
(llvm::CodeGenOptLevel::Aggressive, ..) => {
llvm::LLVMPassManagerBuilderUseInlinerWithThreshold(builder, 275);
llvm::LLVMRustPassManagerBuilderUseInlinerWithThreshold(builder, 275);
}
(_, llvm::CodeGenOptSizeDefault, _) => {
llvm::LLVMPassManagerBuilderUseInlinerWithThreshold(builder, 75);
llvm::LLVMRustPassManagerBuilderUseInlinerWithThreshold(builder, 75);
}
(_, llvm::CodeGenOptSizeAggressive, _) => {
llvm::LLVMPassManagerBuilderUseInlinerWithThreshold(builder, 25);
llvm::LLVMRustPassManagerBuilderUseInlinerWithThreshold(builder, 25);
}
(llvm::CodeGenOptLevel::None, ..) => {
llvm::LLVMRustAddAlwaysInlinePass(builder, config.emit_lifetime_markers);
@ -1136,12 +1137,12 @@ pub unsafe fn with_llvm_pmb(
llvm::LLVMRustAddAlwaysInlinePass(builder, config.emit_lifetime_markers);
}
(llvm::CodeGenOptLevel::Default, ..) => {
llvm::LLVMPassManagerBuilderUseInlinerWithThreshold(builder, 225);
llvm::LLVMRustPassManagerBuilderUseInlinerWithThreshold(builder, 225);
}
}
f(builder);
llvm::LLVMPassManagerBuilderDispose(builder);
llvm::LLVMRustPassManagerBuilderDispose(builder);
}
// Create a `__imp_<symbol> = &symbol` global for every public static `symbol`.

15
compiler/rustc_codegen_llvm/src/llvm/ffi.rs
View file

@ -1825,24 +1825,22 @@ extern "C" {
pub fn LLVMAddAnalysisPasses<'a>(T: &'a TargetMachine, PM: &PassManager<'a>);
pub fn LLVMPassManagerBuilderCreate() -> &'static mut PassManagerBuilder;
pub fn LLVMPassManagerBuilderDispose(PMB: &'static mut PassManagerBuilder);
pub fn LLVMPassManagerBuilderSetSizeLevel(PMB: &PassManagerBuilder, Value: Bool);
pub fn LLVMPassManagerBuilderSetDisableUnrollLoops(PMB: &PassManagerBuilder, Value: Bool);
pub fn LLVMPassManagerBuilderUseInlinerWithThreshold(
pub fn LLVMRustPassManagerBuilderCreate() -> &'static mut PassManagerBuilder;
pub fn LLVMRustPassManagerBuilderDispose(PMB: &'static mut PassManagerBuilder);
pub fn LLVMRustPassManagerBuilderUseInlinerWithThreshold(
PMB: &PassManagerBuilder,
threshold: c_uint,
);
pub fn LLVMPassManagerBuilderPopulateModulePassManager(
pub fn LLVMRustPassManagerBuilderPopulateModulePassManager(
PMB: &PassManagerBuilder,
PM: &PassManager<'_>,
);
pub fn LLVMPassManagerBuilderPopulateFunctionPassManager(
pub fn LLVMRustPassManagerBuilderPopulateFunctionPassManager(
PMB: &PassManagerBuilder,
PM: &PassManager<'_>,
);
pub fn LLVMPassManagerBuilderPopulateLTOPassManager(
pub fn LLVMRustPassManagerBuilderPopulateLTOPassManager(
PMB: &PassManagerBuilder,
PM: &PassManager<'_>,
Internalize: Bool,
@ -2308,6 +2306,7 @@ extern "C" {
PGOGenPath: *const c_char,
PGOUsePath: *const c_char,
PGOSampleUsePath: *const c_char,
SizeLevel: c_int,
);
pub fn LLVMRustAddLibraryInfo<'a>(
PM: &PassManager<'a>,

5
compiler/rustc_codegen_llvm/src/llvm_util.rs
View file

@ -542,6 +542,11 @@ pub(crate) fn should_use_new_llvm_pass_manager(user_opt: &Option<bool>, target_a
// The new pass manager is enabled by default for LLVM >= 13.
// This matches Clang, which also enables it since Clang 13.
// Since LLVM 15, the legacy pass manager is no longer supported.
if llvm_util::get_version() >= (15, 0, 0) {
return true;
}
// There are some perf issues with the new pass manager when targeting
// s390x with LLVM 13, so enable the new pass manager only with LLVM 14.
// See https://github.com/rust-lang/rust/issues/89609.