winch: Use correct heap types in explicit bounds checks (#8157)

This commit is a follow-up to https://github.com/bytecodealliance/wasmtime/pull/8059. Instead of arbitrarily using the target's pointer size, it derives the use from the heap information, in order to do bounds check calculations, this enables checking the right limits.

winch/codegen/src/codegen/bounds.rs

@@ -125,7 +125,7 @@ pub(crate) fn ensure_index_and_offset<M: MacroAssembler>(
     masm: &mut M,
     index: Index,
     offset: u64,
-    ptr_size: OperandSize,
+    heap_ty_size: OperandSize,
 ) -> ImmOffset {
     match u32::try_from(offset) {
         // If the immediate offset fits in a u32, then we simply return.
@@ -137,7 +137,7 @@ pub(crate) fn ensure_index_and_offset<M: MacroAssembler>(
                 index.as_typed_reg().into(),
                 index.as_typed_reg().into(),
                 RegImm::i64(offset as i64),
-                ptr_size,
+                heap_ty_size,
                 TrapCode::HeapOutOfBounds,
             );
 

winch/codegen/src/codegen/mod.rs

@@ -492,7 +492,8 @@ where
         let memory_index = MemoryIndex::from_u32(memarg.memory);
         let heap = self.env.resolve_heap(memory_index);
         let index = Index::from_typed_reg(self.context.pop_to_reg(self.masm, None));
-        let offset = bounds::ensure_index_and_offset(self.masm, index, memarg.offset, ptr_size);
+        let offset =
+            bounds::ensure_index_and_offset(self.masm, index, memarg.offset, heap.ty.into());
         let offset_with_access_size = add_offset_and_access_size(offset, access_size);
 
         let addr = match heap.style {
@@ -528,7 +529,7 @@ where
                     index_offset_and_access_size,
                     index_offset_and_access_size,
                     RegImm::i64(offset_with_access_size as i64),
-                    ptr_size,
+                    heap.ty.into(),
                     TrapCode::HeapOutOfBounds,
                 );
 
@@ -627,7 +628,11 @@ where
                     |masm, bounds, index| {
                         let adjusted_bounds = bounds.as_u64() - offset_with_access_size;
                         let index_reg = index.as_typed_reg().reg;
-                        masm.cmp(RegImm::i64(adjusted_bounds as i64), index_reg, ptr_size);
+                        masm.cmp(
+                            RegImm::i64(adjusted_bounds as i64),
+                            index_reg,
+                            heap.ty.into(),
+                        );
                         IntCmpKind::GtU
                     },
                 );