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CFI: Use Instance at callsites
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We already use `Instance` at declaration sites when available to glean
additional information about possible abstractions of the type in use.
This does the same when possible at callsites as well.

The primary purpose of this change is to allow CFI to alter how it
generates type information for indirect calls through `Virtual`
instances.
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@maurer
maurer committed Mar 22, 2024
1 parent b3df0d7 commit 90e363a
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Showing 11 changed files with 105 additions and 54 deletions.
2 changes: 1 addition & 1 deletion compiler/rustc_codegen_gcc/src/asm.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -541,7 +541,7 @@ impl<'a, 'gcc, 'tcx> AsmBuilderMethods<'tcx> for Builder<'a, 'gcc, 'tcx> {
let builtin_unreachable: RValue<'gcc> = unsafe {
std::mem::transmute(builtin_unreachable)
};
self.call(self.type_void(), None, None, builtin_unreachable, &[], None);
self.call(self.type_void(), None, None, builtin_unreachable, &[], None, None);
}

// Write results to outputs.
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6 changes: 4 additions & 2 deletions compiler/rustc_codegen_gcc/src/builder.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -25,7 +25,7 @@ use rustc_middle::ty::layout::{
FnAbiError, FnAbiOfHelpers, FnAbiRequest, HasParamEnv, HasTyCtxt, LayoutError, LayoutOfHelpers,
TyAndLayout,
};
use rustc_middle::ty::{ParamEnv, Ty, TyCtxt};
use rustc_middle::ty::{ParamEnv, Ty, TyCtxt, Instance};
use rustc_span::def_id::DefId;
use rustc_span::Span;
use rustc_target::abi::{
Expand Down Expand Up @@ -592,12 +592,13 @@ impl<'a, 'gcc, 'tcx> BuilderMethods<'a, 'tcx> for Builder<'a, 'gcc, 'tcx> {
then: Block<'gcc>,
catch: Block<'gcc>,
_funclet: Option<&Funclet>,
instance: Option<Instance<'tcx>>,
) -> RValue<'gcc> {
let try_block = self.current_func().new_block("try");

let current_block = self.block.clone();
self.block = try_block;
let call = self.call(typ, fn_attrs, None, func, args, None); // TODO(antoyo): use funclet here?
let call = self.call(typ, fn_attrs, None, func, args, None, instance); // TODO(antoyo): use funclet here?
self.block = current_block;

let return_value =
Expand Down Expand Up @@ -1667,6 +1668,7 @@ impl<'a, 'gcc, 'tcx> BuilderMethods<'a, 'tcx> for Builder<'a, 'gcc, 'tcx> {
func: RValue<'gcc>,
args: &[RValue<'gcc>],
funclet: Option<&Funclet>,
_instance: Option<Instance<'tcx>>,
) -> RValue<'gcc> {
// FIXME(antoyo): remove when having a proper API.
let gcc_func = unsafe { std::mem::transmute(func) };
Expand Down
11 changes: 6 additions & 5 deletions compiler/rustc_codegen_gcc/src/intrinsic/mod.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -133,6 +133,7 @@ impl<'a, 'gcc, 'tcx> IntrinsicCallMethods<'tcx> for Builder<'a, 'gcc, 'tcx> {
func,
&args.iter().map(|arg| arg.immediate()).collect::<Vec<_>>(),
None,
None,
)
}
sym::likely => self.expect(args[0].immediate(), true),
Expand Down Expand Up @@ -401,7 +402,7 @@ impl<'a, 'gcc, 'tcx> IntrinsicCallMethods<'tcx> for Builder<'a, 'gcc, 'tcx> {
fn abort(&mut self) {
let func = self.context.get_builtin_function("abort");
let func: RValue<'gcc> = unsafe { std::mem::transmute(func) };
self.call(self.type_void(), None, None, func, &[], None);
self.call(self.type_void(), None, None, func, &[], None, None);
}

fn assume(&mut self, value: Self::Value) {
Expand Down Expand Up @@ -1103,7 +1104,7 @@ fn try_intrinsic<'a, 'b, 'gcc, 'tcx>(
dest: RValue<'gcc>,
) {
if bx.sess().panic_strategy() == PanicStrategy::Abort {
bx.call(bx.type_void(), None, None, try_func, &[data], None);
bx.call(bx.type_void(), None, None, try_func, &[data], None, None);
// Return 0 unconditionally from the intrinsic call;
// we can never unwind.
let ret_align = bx.tcx.data_layout.i32_align.abi;
Expand Down Expand Up @@ -1177,21 +1178,21 @@ fn codegen_gnu_try<'gcc>(
let zero = bx.cx.context.new_rvalue_zero(bx.int_type);
let ptr = bx.cx.context.new_call(None, eh_pointer_builtin, &[zero]);
let catch_ty = bx.type_func(&[bx.type_i8p(), bx.type_i8p()], bx.type_void());
bx.call(catch_ty, None, None, catch_func, &[data, ptr], None);
bx.call(catch_ty, None, None, catch_func, &[data, ptr], None, None);
bx.ret(bx.const_i32(1));

// NOTE: the blocks must be filled before adding the try/catch, otherwise gcc will not
// generate a try/catch.
// FIXME(antoyo): add a check in the libgccjit API to prevent this.
bx.switch_to_block(current_block);
bx.invoke(try_func_ty, None, None, try_func, &[data], then, catch, None);
bx.invoke(try_func_ty, None, None, try_func, &[data], then, catch, None, None);
});

let func = unsafe { std::mem::transmute(func) };

// Note that no invoke is used here because by definition this function
// can't panic (that's what it's catching).
let ret = bx.call(llty, None, None, func, &[try_func, data, catch_func], None);
let ret = bx.call(llty, None, None, func, &[try_func, data, catch_func], None, None);
let i32_align = bx.tcx().data_layout.i32_align.abi;
bx.store(ret, dest, i32_align);
}
Expand Down
6 changes: 3 additions & 3 deletions compiler/rustc_codegen_llvm/src/asm.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -466,11 +466,11 @@ pub(crate) fn inline_asm_call<'ll>(

let call = if !labels.is_empty() {
assert!(catch_funclet.is_none());
bx.callbr(fty, None, None, v, inputs, dest.unwrap(), labels, None)
bx.callbr(fty, None, None, v, inputs, dest.unwrap(), labels, None, None)
} else if let Some((catch, funclet)) = catch_funclet {
bx.invoke(fty, None, None, v, inputs, dest.unwrap(), catch, funclet)
bx.invoke(fty, None, None, v, inputs, dest.unwrap(), catch, funclet, None)
} else {
bx.call(fty, None, None, v, inputs, None)
bx.call(fty, None, None, v, inputs, None, None)
};

// Store mark in a metadata node so we can map LLVM errors
Expand Down
41 changes: 29 additions & 12 deletions compiler/rustc_codegen_llvm/src/builder.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -19,9 +19,12 @@ use rustc_middle::middle::codegen_fn_attrs::CodegenFnAttrs;
use rustc_middle::ty::layout::{
FnAbiError, FnAbiOfHelpers, FnAbiRequest, LayoutError, LayoutOfHelpers, TyAndLayout,
};
use rustc_middle::ty::{self, Ty, TyCtxt};
use rustc_middle::ty::{self, Instance, Ty, TyCtxt};
use rustc_span::Span;
use rustc_symbol_mangling::typeid::{kcfi_typeid_for_fnabi, typeid_for_fnabi, TypeIdOptions};
use rustc_symbol_mangling::typeid::{
kcfi_typeid_for_fnabi, kcfi_typeid_for_instance, typeid_for_fnabi, typeid_for_instance,
TypeIdOptions,
};
use rustc_target::abi::{self, call::FnAbi, Align, Size, WrappingRange};
use rustc_target::spec::{HasTargetSpec, SanitizerSet, Target};
use smallvec::SmallVec;
Expand Down Expand Up @@ -221,6 +224,7 @@ impl<'a, 'll, 'tcx> BuilderMethods<'a, 'tcx> for Builder<'a, 'll, 'tcx> {
then: &'ll BasicBlock,
catch: &'ll BasicBlock,
funclet: Option<&Funclet<'ll>>,
instance: Option<Instance<'tcx>>,
) -> &'ll Value {
debug!("invoke {:?} with args ({:?})", llfn, args);

Expand All @@ -233,10 +237,10 @@ impl<'a, 'll, 'tcx> BuilderMethods<'a, 'tcx> for Builder<'a, 'll, 'tcx> {
}

// Emit CFI pointer type membership test
self.cfi_type_test(fn_attrs, fn_abi, llfn);
self.cfi_type_test(fn_attrs, fn_abi, instance, llfn);

// Emit KCFI operand bundle
let kcfi_bundle = self.kcfi_operand_bundle(fn_attrs, fn_abi, llfn);
let kcfi_bundle = self.kcfi_operand_bundle(fn_attrs, fn_abi, instance, llfn);
let kcfi_bundle = kcfi_bundle.as_ref().map(|b| &*b.raw);
if let Some(kcfi_bundle) = kcfi_bundle {
bundles.push(kcfi_bundle);
Expand Down Expand Up @@ -1231,6 +1235,7 @@ impl<'a, 'll, 'tcx> BuilderMethods<'a, 'tcx> for Builder<'a, 'll, 'tcx> {
llfn: &'ll Value,
args: &[&'ll Value],
funclet: Option<&Funclet<'ll>>,
instance: Option<Instance<'tcx>>,
) -> &'ll Value {
debug!("call {:?} with args ({:?})", llfn, args);

Expand All @@ -1243,10 +1248,10 @@ impl<'a, 'll, 'tcx> BuilderMethods<'a, 'tcx> for Builder<'a, 'll, 'tcx> {
}

// Emit CFI pointer type membership test
self.cfi_type_test(fn_attrs, fn_abi, llfn);
self.cfi_type_test(fn_attrs, fn_abi, instance, llfn);

// Emit KCFI operand bundle
let kcfi_bundle = self.kcfi_operand_bundle(fn_attrs, fn_abi, llfn);
let kcfi_bundle = self.kcfi_operand_bundle(fn_attrs, fn_abi, instance, llfn);
let kcfi_bundle = kcfi_bundle.as_ref().map(|b| &*b.raw);
if let Some(kcfi_bundle) = kcfi_bundle {
bundles.push(kcfi_bundle);
Expand Down Expand Up @@ -1468,7 +1473,7 @@ impl<'a, 'll, 'tcx> Builder<'a, 'll, 'tcx> {

pub(crate) fn call_intrinsic(&mut self, intrinsic: &str, args: &[&'ll Value]) -> &'ll Value {
let (ty, f) = self.cx.get_intrinsic(intrinsic);
self.call(ty, None, None, f, args, None)
self.call(ty, None, None, f, args, None, None)
}

fn call_lifetime_intrinsic(&mut self, intrinsic: &str, ptr: &'ll Value, size: Size) {
Expand Down Expand Up @@ -1526,7 +1531,7 @@ impl<'a, 'll, 'tcx> Builder<'a, 'll, 'tcx> {
format!("llvm.{instr}.sat.i{int_width}.f{float_width}")
};
let f = self.declare_cfn(&name, llvm::UnnamedAddr::No, self.type_func(&[src_ty], dest_ty));
self.call(self.type_func(&[src_ty], dest_ty), None, None, f, &[val], None)
self.call(self.type_func(&[src_ty], dest_ty), None, None, f, &[val], None, None)
}

pub(crate) fn landing_pad(
Expand Down Expand Up @@ -1554,6 +1559,7 @@ impl<'a, 'll, 'tcx> Builder<'a, 'll, 'tcx> {
default_dest: &'ll BasicBlock,
indirect_dest: &[&'ll BasicBlock],
funclet: Option<&Funclet<'ll>>,
instance: Option<Instance<'tcx>>,
) -> &'ll Value {
debug!("invoke {:?} with args ({:?})", llfn, args);

Expand All @@ -1566,10 +1572,10 @@ impl<'a, 'll, 'tcx> Builder<'a, 'll, 'tcx> {
}

// Emit CFI pointer type membership test
self.cfi_type_test(fn_attrs, fn_abi, llfn);
self.cfi_type_test(fn_attrs, fn_abi, instance, llfn);

// Emit KCFI operand bundle
let kcfi_bundle = self.kcfi_operand_bundle(fn_attrs, fn_abi, llfn);
let kcfi_bundle = self.kcfi_operand_bundle(fn_attrs, fn_abi, instance, llfn);
let kcfi_bundle = kcfi_bundle.as_ref().map(|b| &*b.raw);
if let Some(kcfi_bundle) = kcfi_bundle {
bundles.push(kcfi_bundle);
Expand Down Expand Up @@ -1601,6 +1607,7 @@ impl<'a, 'll, 'tcx> Builder<'a, 'll, 'tcx> {
&mut self,
fn_attrs: Option<&CodegenFnAttrs>,
fn_abi: Option<&FnAbi<'tcx, Ty<'tcx>>>,
instance: Option<Instance<'tcx>>,
llfn: &'ll Value,
) {
let is_indirect_call = unsafe { llvm::LLVMRustIsNonGVFunctionPointerTy(llfn) };
Expand All @@ -1622,7 +1629,11 @@ impl<'a, 'll, 'tcx> Builder<'a, 'll, 'tcx> {
options.insert(TypeIdOptions::NORMALIZE_INTEGERS);
}

let typeid = typeid_for_fnabi(self.tcx, fn_abi, options);
let typeid = if let Some(instance) = instance {
typeid_for_instance(self.tcx, &instance, options)
} else {
typeid_for_fnabi(self.tcx, fn_abi, options)
};
let typeid_metadata = self.cx.typeid_metadata(typeid).unwrap();

// Test whether the function pointer is associated with the type identifier.
Expand All @@ -1644,6 +1655,7 @@ impl<'a, 'll, 'tcx> Builder<'a, 'll, 'tcx> {
&mut self,
fn_attrs: Option<&CodegenFnAttrs>,
fn_abi: Option<&FnAbi<'tcx, Ty<'tcx>>>,
instance: Option<Instance<'tcx>>,
llfn: &'ll Value,
) -> Option<llvm::OperandBundleDef<'ll>> {
let is_indirect_call = unsafe { llvm::LLVMRustIsNonGVFunctionPointerTy(llfn) };
Expand All @@ -1665,7 +1677,12 @@ impl<'a, 'll, 'tcx> Builder<'a, 'll, 'tcx> {
options.insert(TypeIdOptions::NORMALIZE_INTEGERS);
}

let kcfi_typeid = kcfi_typeid_for_fnabi(self.tcx, fn_abi, options);
let kcfi_typeid = if let Some(instance) = instance {
kcfi_typeid_for_instance(self.tcx, &instance, options)
} else {
kcfi_typeid_for_fnabi(self.tcx, fn_abi, options)
};

Some(llvm::OperandBundleDef::new("kcfi", &[self.const_u32(kcfi_typeid)]))
} else {
None
Expand Down
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