diff --git a/compiler/rustc_const_eval/src/interpret/intrinsics/simd.rs b/compiler/rustc_const_eval/src/interpret/intrinsics/simd.rs index 0dba66ae93721..f14ab3ecb9050 100644 --- a/compiler/rustc_const_eval/src/interpret/intrinsics/simd.rs +++ b/compiler/rustc_const_eval/src/interpret/intrinsics/simd.rs @@ -2,7 +2,7 @@ use either::Either; use rustc_abi::Endian; use rustc_apfloat::{Float, Round}; use rustc_middle::mir::interpret::{InterpErrorKind, UndefinedBehaviorInfo}; -use rustc_middle::ty::FloatTy; +use rustc_middle::ty::{FloatTy, ScalarInt}; use rustc_middle::{bug, err_ub_format, mir, span_bug, throw_unsup_format, ty}; use rustc_span::{Symbol, sym}; use tracing::trace; @@ -701,6 +701,44 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> { }; } } + sym::simd_funnel_shl | sym::simd_funnel_shr => { + let (left, _) = self.project_to_simd(&args[0])?; + let (right, _) = self.project_to_simd(&args[1])?; + let (shift, _) = self.project_to_simd(&args[2])?; + let (dest, _) = self.project_to_simd(&dest)?; + + let (len, elem_ty) = args[0].layout.ty.simd_size_and_type(*self.tcx); + let (elem_size, _signed) = elem_ty.int_size_and_signed(*self.tcx); + let elem_size_bits = elem_size.bits() as u128; + + let is_left = intrinsic_name == sym::simd_funnel_shl; + + for i in 0..len { + let left = + self.read_scalar(&self.project_index(&left, i)?)?.to_bits(elem_size)?; + let right = + self.read_scalar(&self.project_index(&right, i)?)?.to_bits(elem_size)?; + let shift_bits = + self.read_scalar(&self.project_index(&shift, i)?)?.to_bits(elem_size)?; + + if shift_bits >= elem_size_bits { + err_ub_format!( + "overflowing shift by {shift_bits} in `{intrinsic_name}` in lane {i}" + ); + } + let inv_shift_bits = (elem_size_bits - shift_bits) as u32; + + let result_bits = if is_left { + (left << shift_bits) | right.unbounded_shr(inv_shift_bits) + } else { + left.unbounded_shl(inv_shift_bits) | (right >> shift_bits) + }; + let (result, _overflow) = ScalarInt::truncate_from_uint(result_bits, elem_size); + + let dest = self.project_index(&dest, i)?; + self.write_scalar(result, &dest)?; + } + } // Unsupported intrinsic: skip the return_to_block below. _ => return interp_ok(false),