Avoid mir_operand_get_const_val for simd_shuffle and cmpps and cmppd

Author: bjorn3

src/intrinsics/llvm_x86.rs

@@ -74,8 +74,12 @@ pub(crate) fn codegen_x86_llvm_intrinsic_call<'tcx>(
             };
             let x = codegen_operand(fx, x);
             let y = codegen_operand(fx, y);
-            let kind = crate::constant::mir_operand_get_const_val(fx, kind)
-                .expect("llvm.x86.sse2.cmp.* kind not const");
+            let kind = match kind {
+                Operand::Constant(const_) => {
+                    crate::constant::eval_mir_constant(fx, const_).unwrap().0
+                }
+                Operand::Copy(_) | Operand::Move(_) => unreachable!("{kind:?}"),
+            };
 
             let flt_cc = match kind
                 .try_to_bits(Size::from_bytes(1))

src/intrinsics/simd.rs

@@ -168,8 +168,12 @@ pub(super) fn codegen_simd_intrinsic_call<'tcx>(
 
             let indexes = {
                 use rustc_middle::mir::interpret::*;
-                let idx_const = crate::constant::mir_operand_get_const_val(fx, idx)
-                    .expect("simd_shuffle idx not const");
+                let idx_const = match idx {
+                    Operand::Constant(const_) => {
+                        crate::constant::eval_mir_constant(fx, const_).unwrap().0
+                    }
+                    Operand::Copy(_) | Operand::Move(_) => unreachable!("{idx:?}"),
+                };
 
                 let idx_bytes = match idx_const {
                     ConstValue::ByRef { alloc, offset } => {