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Auto merge of #109507 - Amanieu:panic-oom-payload, r=davidtwco

Report allocation errors as panics

OOM is now reported as a panic but with a custom payload type (`AllocErrorPanicPayload`) which holds the layout that was passed to `handle_alloc_error`.

This should be review one commit at a time:
- The first commit adds `AllocErrorPanicPayload` and changes allocation errors to always be reported as panics.
- The second commit removes `#[alloc_error_handler]` and the `alloc_error_hook` API.

ACP: https://github.com/rust-lang/libs-team/issues/192

Closes #51540
Closes #51245
This commit is contained in:
bors 2023-04-22 12:27:45 +00:00
commit 39cf520299
58 changed files with 138 additions and 878 deletions

View file

@ -4,7 +4,6 @@ use rustc_ast::expand::allocator::{AllocatorKind, AllocatorTy, ALLOCATOR_METHODS
use rustc_middle::bug;
use rustc_middle::ty::TyCtxt;
use rustc_session::config::{DebugInfo, OomStrategy};
use rustc_span::symbol::sym;
use crate::debuginfo;
use crate::llvm::{self, False, True};
@ -15,7 +14,6 @@ pub(crate) unsafe fn codegen(
module_llvm: &mut ModuleLlvm,
module_name: &str,
kind: AllocatorKind,
alloc_error_handler_kind: AllocatorKind,
) {
let llcx = &*module_llvm.llcx;
let llmod = module_llvm.llmod();
@ -100,52 +98,6 @@ pub(crate) unsafe fn codegen(
llvm::LLVMDisposeBuilder(llbuilder);
}
// rust alloc error handler
let args = [usize, usize]; // size, align
let ty = llvm::LLVMFunctionType(void, args.as_ptr(), args.len() as c_uint, False);
let name = "__rust_alloc_error_handler";
let llfn = llvm::LLVMRustGetOrInsertFunction(llmod, name.as_ptr().cast(), name.len(), ty);
// -> ! DIFlagNoReturn
let no_return = llvm::AttributeKind::NoReturn.create_attr(llcx);
attributes::apply_to_llfn(llfn, llvm::AttributePlace::Function, &[no_return]);
if tcx.sess.target.default_hidden_visibility {
llvm::LLVMRustSetVisibility(llfn, llvm::Visibility::Hidden);
}
if tcx.sess.must_emit_unwind_tables() {
let uwtable = attributes::uwtable_attr(llcx);
attributes::apply_to_llfn(llfn, llvm::AttributePlace::Function, &[uwtable]);
}
let callee = alloc_error_handler_kind.fn_name(sym::oom);
let callee = llvm::LLVMRustGetOrInsertFunction(llmod, callee.as_ptr().cast(), callee.len(), ty);
// -> ! DIFlagNoReturn
attributes::apply_to_llfn(callee, llvm::AttributePlace::Function, &[no_return]);
llvm::LLVMRustSetVisibility(callee, llvm::Visibility::Hidden);
let llbb = llvm::LLVMAppendBasicBlockInContext(llcx, llfn, "entry\0".as_ptr().cast());
let llbuilder = llvm::LLVMCreateBuilderInContext(llcx);
llvm::LLVMPositionBuilderAtEnd(llbuilder, llbb);
let args = args
.iter()
.enumerate()
.map(|(i, _)| llvm::LLVMGetParam(llfn, i as c_uint))
.collect::<Vec<_>>();
let ret = llvm::LLVMRustBuildCall(
llbuilder,
ty,
callee,
args.as_ptr(),
args.len() as c_uint,
[].as_ptr(),
0 as c_uint,
);
llvm::LLVMSetTailCall(ret, True);
llvm::LLVMBuildRetVoid(llbuilder);
llvm::LLVMDisposeBuilder(llbuilder);
// __rust_alloc_error_handler_should_panic
let name = OomStrategy::SYMBOL;
let ll_g = llvm::LLVMRustGetOrInsertGlobal(llmod, name.as_ptr().cast(), name.len(), i8);

View file

@ -115,11 +115,10 @@ impl ExtraBackendMethods for LlvmCodegenBackend {
tcx: TyCtxt<'tcx>,
module_name: &str,
kind: AllocatorKind,
alloc_error_handler_kind: AllocatorKind,
) -> ModuleLlvm {
let mut module_llvm = ModuleLlvm::new_metadata(tcx, module_name);
unsafe {
allocator::codegen(tcx, &mut module_llvm, module_name, kind, alloc_error_handler_kind);
allocator::codegen(tcx, &mut module_llvm, module_name, kind);
}
module_llvm
}