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mir: Add a new method to statement

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Avoid introducing a large number of changes when adding optional initialization fields.
This commit is contained in:
dianqk
2025-06-08 15:30:18 +08:00
parent 5ca574e85b
commit 9f9cd5e283
30 changed files with 295 additions and 330 deletions
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34
compiler/rustc_mir_transform/src/check_alignment.rs
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@@ -51,22 +51,18 @@ fn insert_alignment_check<'tcx>(
let const_raw_ptr = Ty::new_imm_ptr(tcx, tcx.types.unit);
let rvalue = Rvalue::Cast(CastKind::PtrToPtr, Operand::Copy(pointer), const_raw_ptr);
let thin_ptr = local_decls.push(LocalDecl::with_source_info(const_raw_ptr, source_info)).into();
stmts
.push(Statement { source_info, kind: StatementKind::Assign(Box::new((thin_ptr, rvalue))) });
stmts.push(Statement::new(source_info, StatementKind::Assign(Box::new((thin_ptr, rvalue)))));
// Transmute the pointer to a usize (equivalent to `ptr.addr()`).
let rvalue = Rvalue::Cast(CastKind::Transmute, Operand::Copy(thin_ptr), tcx.types.usize);
let addr = local_decls.push(LocalDecl::with_source_info(tcx.types.usize, source_info)).into();
stmts.push(Statement { source_info, kind: StatementKind::Assign(Box::new((addr, rvalue))) });
stmts.push(Statement::new(source_info, StatementKind::Assign(Box::new((addr, rvalue)))));
// Get the alignment of the pointee
let alignment =
local_decls.push(LocalDecl::with_source_info(tcx.types.usize, source_info)).into();
let rvalue = Rvalue::NullaryOp(NullOp::AlignOf, pointee_ty);
stmts.push(Statement {
source_info,
kind: StatementKind::Assign(Box::new((alignment, rvalue))),
});
stmts.push(Statement::new(source_info, StatementKind::Assign(Box::new((alignment, rvalue)))));
// Subtract 1 from the alignment to get the alignment mask
let alignment_mask =
@@ -76,13 +72,13 @@ fn insert_alignment_check<'tcx>(
user_ty: None,
const_: Const::Val(ConstValue::Scalar(Scalar::from_target_usize(1, &tcx)), tcx.types.usize),
}));
stmts.push(Statement {
stmts.push(Statement::new(
source_info,
kind: StatementKind::Assign(Box::new((
StatementKind::Assign(Box::new((
alignment_mask,
Rvalue::BinaryOp(BinOp::Sub, Box::new((Operand::Copy(alignment), one))),
))),
});
));
// If this target does not have reliable alignment, further limit the mask by anding it with
// the mask for the highest reliable alignment.
@@ -99,31 +95,31 @@ fn insert_alignment_check<'tcx>(
tcx.types.usize,
),
}));
stmts.push(Statement {
stmts.push(Statement::new(
source_info,
kind: StatementKind::Assign(Box::new((
StatementKind::Assign(Box::new((
alignment_mask,
Rvalue::BinaryOp(
BinOp::BitAnd,
Box::new((Operand::Copy(alignment_mask), max_mask)),
),
))),
});
));
}
// BitAnd the alignment mask with the pointer
let alignment_bits =
local_decls.push(LocalDecl::with_source_info(tcx.types.usize, source_info)).into();
stmts.push(Statement {
stmts.push(Statement::new(
source_info,
kind: StatementKind::Assign(Box::new((
StatementKind::Assign(Box::new((
alignment_bits,
Rvalue::BinaryOp(
BinOp::BitAnd,
Box::new((Operand::Copy(addr), Operand::Copy(alignment_mask))),
),
))),
});
));
// Check if the alignment bits are all zero
let is_ok = local_decls.push(LocalDecl::with_source_info(tcx.types.bool, source_info)).into();
@@ -132,13 +128,13 @@ fn insert_alignment_check<'tcx>(
user_ty: None,
const_: Const::Val(ConstValue::Scalar(Scalar::from_target_usize(0, &tcx)), tcx.types.usize),
}));
stmts.push(Statement {
stmts.push(Statement::new(
source_info,
kind: StatementKind::Assign(Box::new((
StatementKind::Assign(Box::new((
is_ok,
Rvalue::BinaryOp(BinOp::Eq, Box::new((Operand::Copy(alignment_bits), zero.clone()))),
))),
});
));
// Emit a check that asserts on the alignment and otherwise triggers a
// AssertKind::MisalignedPointerDereference.