diff options
Diffstat (limited to 'compiler/rustc_codegen_ssa/src/mir/rvalue.rs')
| -rw-r--r-- | compiler/rustc_codegen_ssa/src/mir/rvalue.rs | 95 |
1 files changed, 86 insertions, 9 deletions
diff --git a/compiler/rustc_codegen_ssa/src/mir/rvalue.rs b/compiler/rustc_codegen_ssa/src/mir/rvalue.rs index d88226f5d..6e7065713 100644 --- a/compiler/rustc_codegen_ssa/src/mir/rvalue.rs +++ b/compiler/rustc_codegen_ssa/src/mir/rvalue.rs @@ -12,6 +12,7 @@ use rustc_middle::mir::Operand; use rustc_middle::ty::cast::{CastTy, IntTy}; use rustc_middle::ty::layout::{HasTyCtxt, LayoutOf, TyAndLayout}; use rustc_middle::ty::{self, adjustment::PointerCast, Instance, Ty, TyCtxt}; +use rustc_session::config::OptLevel; use rustc_span::source_map::{Span, DUMMY_SP}; use rustc_target::abi::{self, FIRST_VARIANT}; @@ -231,10 +232,16 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> { (ScalarOrZst::Scalar(in_scalar), ScalarOrZst::Scalar(out_scalar)) if in_scalar.size(self.cx) == out_scalar.size(self.cx) => { + let operand_bty = bx.backend_type(operand.layout); let cast_bty = bx.backend_type(cast); - Some(OperandValue::Immediate( - self.transmute_immediate(bx, imm, in_scalar, out_scalar, cast_bty), - )) + Some(OperandValue::Immediate(self.transmute_immediate( + bx, + imm, + in_scalar, + operand_bty, + out_scalar, + cast_bty, + ))) } _ => None, } @@ -250,11 +257,13 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> { && in_a.size(self.cx) == out_a.size(self.cx) && in_b.size(self.cx) == out_b.size(self.cx) { + let in_a_ibty = bx.scalar_pair_element_backend_type(operand.layout, 0, false); + let in_b_ibty = bx.scalar_pair_element_backend_type(operand.layout, 1, false); let out_a_ibty = bx.scalar_pair_element_backend_type(cast, 0, false); let out_b_ibty = bx.scalar_pair_element_backend_type(cast, 1, false); Some(OperandValue::Pair( - self.transmute_immediate(bx, imm_a, in_a, out_a, out_a_ibty), - self.transmute_immediate(bx, imm_b, in_b, out_b, out_b_ibty), + self.transmute_immediate(bx, imm_a, in_a, in_a_ibty, out_a, out_a_ibty), + self.transmute_immediate(bx, imm_b, in_b, in_b_ibty, out_b, out_b_ibty), )) } else { None @@ -273,6 +282,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> { bx: &mut Bx, mut imm: Bx::Value, from_scalar: abi::Scalar, + from_backend_ty: Bx::Type, to_scalar: abi::Scalar, to_backend_ty: Bx::Type, ) -> Bx::Value { @@ -280,6 +290,13 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> { use abi::Primitive::*; imm = bx.from_immediate(imm); + + // When scalars are passed by value, there's no metadata recording their + // valid ranges. For example, `char`s are passed as just `i32`, with no + // way for LLVM to know that they're 0x10FFFF at most. Thus we assume + // the range of the input value too, not just the output range. + self.assume_scalar_range(bx, imm, from_scalar, from_backend_ty); + imm = match (from_scalar.primitive(), to_scalar.primitive()) { (Int(..) | F32 | F64, Int(..) | F32 | F64) => bx.bitcast(imm, to_backend_ty), (Pointer(..), Pointer(..)) => bx.pointercast(imm, to_backend_ty), @@ -294,10 +311,55 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> { bx.bitcast(int_imm, to_backend_ty) } }; + self.assume_scalar_range(bx, imm, to_scalar, to_backend_ty); imm = bx.to_immediate_scalar(imm, to_scalar); imm } + fn assume_scalar_range( + &self, + bx: &mut Bx, + imm: Bx::Value, + scalar: abi::Scalar, + backend_ty: Bx::Type, + ) { + if matches!(self.cx.sess().opts.optimize, OptLevel::No | OptLevel::Less) + // For now, the critical niches are all over `Int`eger values. + // Should floating-point values or pointers ever get more complex + // niches, then this code will probably want to handle them too. + || !matches!(scalar.primitive(), abi::Primitive::Int(..)) + || scalar.is_always_valid(self.cx) + { + return; + } + + let abi::WrappingRange { start, end } = scalar.valid_range(self.cx); + + if start <= end { + if start > 0 { + let low = bx.const_uint_big(backend_ty, start); + let cmp = bx.icmp(IntPredicate::IntUGE, imm, low); + bx.assume(cmp); + } + + let type_max = scalar.size(self.cx).unsigned_int_max(); + if end < type_max { + let high = bx.const_uint_big(backend_ty, end); + let cmp = bx.icmp(IntPredicate::IntULE, imm, high); + bx.assume(cmp); + } + } else { + let low = bx.const_uint_big(backend_ty, start); + let cmp_low = bx.icmp(IntPredicate::IntUGE, imm, low); + + let high = bx.const_uint_big(backend_ty, end); + let cmp_high = bx.icmp(IntPredicate::IntULE, imm, high); + + let or = bx.or(cmp_low, cmp_high); + bx.assume(or); + } + } + pub fn codegen_rvalue_unsized( &mut self, bx: &mut Bx, @@ -604,13 +666,16 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> { } } - mir::Rvalue::NullaryOp(null_op, ty) => { + mir::Rvalue::NullaryOp(ref null_op, ty) => { let ty = self.monomorphize(ty); assert!(bx.cx().type_is_sized(ty)); let layout = bx.cx().layout_of(ty); let val = match null_op { mir::NullOp::SizeOf => layout.size.bytes(), mir::NullOp::AlignOf => layout.align.abi.bytes(), + mir::NullOp::OffsetOf(fields) => { + layout.offset_of_subfield(bx.cx(), fields.iter().map(|f| f.index())).bytes() + } }; let val = bx.cx().const_usize(val); let tcx = self.cx.tcx(); @@ -632,7 +697,12 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> { let fn_ptr = bx.get_fn_addr(instance); let fn_abi = bx.fn_abi_of_instance(instance, ty::List::empty()); let fn_ty = bx.fn_decl_backend_type(&fn_abi); - bx.call(fn_ty, Some(fn_abi), fn_ptr, &[], None) + let fn_attrs = if bx.tcx().def_kind(instance.def_id()).has_codegen_attrs() { + Some(bx.tcx().codegen_fn_attrs(instance.def_id())) + } else { + None + }; + bx.call(fn_ty, fn_attrs, Some(fn_abi), fn_ptr, &[], None) } else { bx.get_static(def_id) }; @@ -754,8 +824,15 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> { .builtin_deref(true) .unwrap_or_else(|| bug!("deref of non-pointer {:?}", input_ty)) .ty; - let llty = bx.cx().backend_type(bx.cx().layout_of(pointee_type)); - bx.inbounds_gep(llty, lhs, &[rhs]) + let pointee_layout = bx.cx().layout_of(pointee_type); + if pointee_layout.is_zst() { + // `Offset` works in terms of the size of pointee, + // so offsetting a pointer to ZST is a noop. + lhs + } else { + let llty = bx.cx().backend_type(pointee_layout); + bx.inbounds_gep(llty, lhs, &[rhs]) + } } mir::BinOp::Shl => common::build_unchecked_lshift(bx, lhs, rhs), mir::BinOp::Shr => common::build_unchecked_rshift(bx, input_ty, lhs, rhs), |