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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 committed Mar 23, 2024
1 parent a951158 commit abbe1ba
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Showing 3 changed files with 11 additions and 8 deletions.
2 changes: 1 addition & 1 deletion src/asm.rs
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 src/builder.rs
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) };
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11 changes: 6 additions & 5 deletions src/intrinsic/mod.rs
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

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