diff options
Diffstat (limited to 'compiler')
| -rw-r--r-- | compiler/rustc_codegen_ssa/src/mir/rvalue.rs | 136 |
1 files changed, 79 insertions, 57 deletions
diff --git a/compiler/rustc_codegen_ssa/src/mir/rvalue.rs b/compiler/rustc_codegen_ssa/src/mir/rvalue.rs index 0cd3e60b0cc..491b457358a 100644 --- a/compiler/rustc_codegen_ssa/src/mir/rvalue.rs +++ b/compiler/rustc_codegen_ssa/src/mir/rvalue.rs @@ -8,7 +8,6 @@ use crate::traits::*; use crate::MemFlags; use rustc_middle::mir; -use rustc_middle::ty::cast::{CastTy, IntTy}; use rustc_middle::ty::layout::{HasTyCtxt, LayoutOf, TyAndLayout}; use rustc_middle::ty::{self, adjustment::PointerCoercion, Instance, Ty, TyCtxt}; use rustc_middle::{bug, span_bug}; @@ -238,21 +237,21 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> { } } OperandValue::Immediate(imm) => { - let OperandValueKind::Immediate(in_scalar) = operand_kind else { + let OperandValueKind::Immediate(from_scalar) = operand_kind else { bug!("Found {operand_kind:?} for operand {operand:?}"); }; - if let OperandValueKind::Immediate(out_scalar) = cast_kind - && in_scalar.size(self.cx) == out_scalar.size(self.cx) + if let OperandValueKind::Immediate(to_scalar) = cast_kind + && from_scalar.size(self.cx) == to_scalar.size(self.cx) { - let operand_bty = bx.backend_type(operand.layout); - let cast_bty = bx.backend_type(cast); + let from_backend_ty = bx.backend_type(operand.layout); + let to_backend_ty = bx.backend_type(cast); Some(OperandValue::Immediate(self.transmute_immediate( bx, imm, - in_scalar, - operand_bty, - out_scalar, - cast_bty, + from_scalar, + from_backend_ty, + to_scalar, + to_backend_ty, ))) } else { None @@ -281,6 +280,58 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> { } } + /// Cast one of the immediates from an [`OperandValue::Immediate`] + /// or an [`OperandValue::Pair`] to an immediate of the target type. + /// + /// Returns `None` if the cast is not possible. + fn cast_immediate( + &self, + 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, + ) -> Option<Bx::Value> { + use abi::Primitive::*; + + // 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(_, is_signed), Int(..)) => bx.intcast(imm, to_backend_ty, is_signed), + (Float(_), Float(_)) => { + let srcsz = bx.cx().float_width(from_backend_ty); + let dstsz = bx.cx().float_width(to_backend_ty); + if dstsz > srcsz { + bx.fpext(imm, to_backend_ty) + } else if srcsz > dstsz { + bx.fptrunc(imm, to_backend_ty) + } else { + imm + } + } + (Int(_, is_signed), Float(_)) => { + if is_signed { + bx.sitofp(imm, to_backend_ty) + } else { + bx.uitofp(imm, to_backend_ty) + } + } + (Pointer(..), Pointer(..)) => bx.pointercast(imm, to_backend_ty), + (Int(_, is_signed), Pointer(..)) => { + let usize_imm = bx.intcast(imm, bx.cx().type_isize(), is_signed); + bx.inttoptr(usize_imm, to_backend_ty) + } + (Float(_), Int(_, is_signed)) => bx.cast_float_to_int(is_signed, imm, to_backend_ty), + _ => return None, + }; + Some(imm) + } + /// Transmutes one of the immediates from an [`OperandValue::Immediate`] /// or an [`OperandValue::Pair`] to an immediate of the target type. /// @@ -487,62 +538,33 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> { | mir::CastKind::IntToFloat | mir::CastKind::PtrToPtr | mir::CastKind::FnPtrToPtr - // Since int2ptr can have arbitrary integer types as input (so we have to do // sign extension and all that), it is currently best handled in the same code // path as the other integer-to-X casts. | mir::CastKind::PointerWithExposedProvenance => { + let imm = operand.immediate(); + let operand_kind = self.value_kind(operand.layout); + let OperandValueKind::Immediate(from_scalar) = operand_kind else { + bug!("Found {operand_kind:?} for operand {operand:?}"); + }; + let from_backend_ty = bx.cx().immediate_backend_type(operand.layout); + assert!(bx.cx().is_backend_immediate(cast)); - let ll_t_out = bx.cx().immediate_backend_type(cast); + let to_backend_ty = bx.cx().immediate_backend_type(cast); if operand.layout.abi.is_uninhabited() { - let val = OperandValue::Immediate(bx.cx().const_poison(ll_t_out)); + let val = OperandValue::Immediate(bx.cx().const_poison(to_backend_ty)); return OperandRef { val, layout: cast }; } - let r_t_in = - CastTy::from_ty(operand.layout.ty).expect("bad input type for cast"); - let r_t_out = CastTy::from_ty(cast.ty).expect("bad output type for cast"); - let ll_t_in = bx.cx().immediate_backend_type(operand.layout); - let llval = operand.immediate(); - - let newval = match (r_t_in, r_t_out) { - (CastTy::Int(i), CastTy::Int(_)) => { - bx.intcast(llval, ll_t_out, i.is_signed()) - } - (CastTy::Float, CastTy::Float) => { - let srcsz = bx.cx().float_width(ll_t_in); - let dstsz = bx.cx().float_width(ll_t_out); - if dstsz > srcsz { - bx.fpext(llval, ll_t_out) - } else if srcsz > dstsz { - bx.fptrunc(llval, ll_t_out) - } else { - llval - } - } - (CastTy::Int(i), CastTy::Float) => { - if i.is_signed() { - bx.sitofp(llval, ll_t_out) - } else { - bx.uitofp(llval, ll_t_out) - } - } - (CastTy::Ptr(_) | CastTy::FnPtr, CastTy::Ptr(_)) => { - bx.pointercast(llval, ll_t_out) - } - (CastTy::Int(i), CastTy::Ptr(_)) => { - let usize_llval = - bx.intcast(llval, bx.cx().type_isize(), i.is_signed()); - bx.inttoptr(usize_llval, ll_t_out) - } - (CastTy::Float, CastTy::Int(IntTy::I)) => { - bx.cast_float_to_int(true, llval, ll_t_out) - } - (CastTy::Float, CastTy::Int(_)) => { - bx.cast_float_to_int(false, llval, ll_t_out) - } - _ => bug!("unsupported cast: {:?} to {:?}", operand.layout.ty, cast.ty), + let cast_kind = self.value_kind(cast); + let OperandValueKind::Immediate(to_scalar) = cast_kind else { + bug!("Found {cast_kind:?} for operand {cast:?}"); }; - OperandValue::Immediate(newval) + + self.cast_immediate(bx, imm, from_scalar, from_backend_ty, to_scalar, to_backend_ty) + .map(OperandValue::Immediate) + .unwrap_or_else(|| { + bug!("Unsupported cast of {operand:?} to {cast:?}"); + }) } mir::CastKind::Transmute => { self.codegen_transmute_operand(bx, operand, cast).unwrap_or_else(|| { |