diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
index 279f0d7..78f25ef 100644
--- a/hw/i386/acpi-build.c
+++ b/hw/i386/acpi-build.c
@@ -736,6 +736,23 @@ static void crs_range_free(gpointer data)
     g_free(entry);
 }
 
+typedef struct CrsRangeSet {
+    GPtrArray *io_ranges;
+    GPtrArray *mem_ranges;
+ } CrsRangeSet;
+
+static void crs_range_set_init(CrsRangeSet *range_set)
+{
+    range_set->io_ranges = g_ptr_array_new_with_free_func(crs_range_free);
+    range_set->mem_ranges = g_ptr_array_new_with_free_func(crs_range_free);
+}
+
+static void crs_range_set_free(CrsRangeSet *range_set)
+{
+    g_ptr_array_free(range_set->io_ranges, true);
+    g_ptr_array_free(range_set->mem_ranges, true);
+}
+
 static gint crs_range_compare(gconstpointer a, gconstpointer b)
 {
      CrsRangeEntry *entry_a = *(CrsRangeEntry **)a;
@@ -820,18 +837,17 @@ static void crs_range_merge(GPtrArray *range)
     g_ptr_array_free(tmp, true);
 }
 
-static Aml *build_crs(PCIHostState *host,
-                      GPtrArray *io_ranges, GPtrArray *mem_ranges)
+static Aml *build_crs(PCIHostState *host, CrsRangeSet *range_set)
 {
     Aml *crs = aml_resource_template();
-    GPtrArray *host_io_ranges = g_ptr_array_new_with_free_func(crs_range_free);
-    GPtrArray *host_mem_ranges = g_ptr_array_new_with_free_func(crs_range_free);
+    CrsRangeSet temp_range_set;
     CrsRangeEntry *entry;
     uint8_t max_bus = pci_bus_num(host->bus);
     uint8_t type;
     int devfn;
     int i;
 
+    crs_range_set_init(&temp_range_set);
     for (devfn = 0; devfn < ARRAY_SIZE(host->bus->devices); devfn++) {
         uint64_t range_base, range_limit;
         PCIDevice *dev = host->bus->devices[devfn];
@@ -855,9 +871,11 @@ static Aml *build_crs(PCIHostState *host,
             }
 
             if (r->type & PCI_BASE_ADDRESS_SPACE_IO) {
-                crs_range_insert(host_io_ranges, range_base, range_limit);
+                crs_range_insert(temp_range_set.io_ranges,
+                                 range_base, range_limit);
             } else { /* "memory" */
-                crs_range_insert(host_mem_ranges, range_base, range_limit);
+                crs_range_insert(temp_range_set.mem_ranges,
+                                 range_base, range_limit);
             }
         }
 
@@ -876,7 +894,8 @@ static Aml *build_crs(PCIHostState *host,
              * that do not support multiple root buses
              */
             if (range_base && range_base <= range_limit) {
-                crs_range_insert(host_io_ranges, range_base, range_limit);
+                crs_range_insert(temp_range_set.io_ranges,
+                                 range_base, range_limit);
             }
 
             range_base =
@@ -889,7 +908,8 @@ static Aml *build_crs(PCIHostState *host,
              * that do not support multiple root buses
              */
             if (range_base && range_base <= range_limit) {
-                crs_range_insert(host_mem_ranges, range_base, range_limit);
+                crs_range_insert(temp_range_set.mem_ranges,
+                                 range_base, range_limit);
             }
 
             range_base =
@@ -902,35 +922,36 @@ static Aml *build_crs(PCIHostState *host,
              * that do not support multiple root buses
              */
             if (range_base && range_base <= range_limit) {
-                crs_range_insert(host_mem_ranges, range_base, range_limit);
+                crs_range_insert(temp_range_set.mem_ranges,
+                                 range_base, range_limit);
             }
         }
     }
 
-    crs_range_merge(host_io_ranges);
-    for (i = 0; i < host_io_ranges->len; i++) {
-        entry = g_ptr_array_index(host_io_ranges, i);
+    crs_range_merge(temp_range_set.io_ranges);
+    for (i = 0; i < temp_range_set.io_ranges->len; i++) {
+        entry = g_ptr_array_index(temp_range_set.io_ranges, i);
         aml_append(crs,
                    aml_word_io(AML_MIN_FIXED, AML_MAX_FIXED,
                                AML_POS_DECODE, AML_ENTIRE_RANGE,
                                0, entry->base, entry->limit, 0,
                                entry->limit - entry->base + 1));
-        crs_range_insert(io_ranges, entry->base, entry->limit);
+        crs_range_insert(range_set->io_ranges, entry->base, entry->limit);
     }
-    g_ptr_array_free(host_io_ranges, true);
 
-    crs_range_merge(host_mem_ranges);
-    for (i = 0; i < host_mem_ranges->len; i++) {
-        entry = g_ptr_array_index(host_mem_ranges, i);
+    crs_range_merge(temp_range_set.mem_ranges);
+    for (i = 0; i < temp_range_set.mem_ranges->len; i++) {
+        entry = g_ptr_array_index(temp_range_set.mem_ranges, i);
         aml_append(crs,
                    aml_dword_memory(AML_POS_DECODE, AML_MIN_FIXED,
                                     AML_MAX_FIXED, AML_NON_CACHEABLE,
                                     AML_READ_WRITE,
                                     0, entry->base, entry->limit, 0,
                                     entry->limit - entry->base + 1));
-        crs_range_insert(mem_ranges, entry->base, entry->limit);
+        crs_range_insert(range_set->mem_ranges, entry->base, entry->limit);
     }
-    g_ptr_array_free(host_mem_ranges, true);
+
+    crs_range_set_free(&temp_range_set);
 
     aml_append(crs,
         aml_word_bus_number(AML_MIN_FIXED, AML_MAX_FIXED, AML_POS_DECODE,
@@ -1985,8 +2006,7 @@ build_dsdt(GArray *table_data, GArray *linker,
 {
     CrsRangeEntry *entry;
     Aml *dsdt, *sb_scope, *scope, *dev, *method, *field, *pkg, *crs;
-    GPtrArray *mem_ranges = g_ptr_array_new_with_free_func(crs_range_free);
-    GPtrArray *io_ranges = g_ptr_array_new_with_free_func(crs_range_free);
+    CrsRangeSet crs_range_set;
     PCMachineState *pcms = PC_MACHINE(machine);
     uint32_t nr_mem = machine->ram_slots;
     int root_bus_limit = 0xFF;
@@ -2087,6 +2107,7 @@ build_dsdt(GArray *table_data, GArray *linker,
     }
     aml_append(dsdt, scope);
 
+    crs_range_set_init(&crs_range_set);
     bus = PC_MACHINE(machine)->bus;
     if (bus) {
         QLIST_FOREACH(bus, &bus->child, sibling) {
@@ -2113,8 +2134,7 @@ build_dsdt(GArray *table_data, GArray *linker,
             }
 
             aml_append(dev, build_prt(false));
-            crs = build_crs(PCI_HOST_BRIDGE(BUS(bus)->parent),
-                            io_ranges, mem_ranges);
+            crs = build_crs(PCI_HOST_BRIDGE(BUS(bus)->parent), &crs_range_set);
             aml_append(dev, aml_name_decl("_CRS", crs));
             aml_append(scope, dev);
             aml_append(dsdt, scope);
@@ -2135,9 +2155,9 @@ build_dsdt(GArray *table_data, GArray *linker,
                     AML_POS_DECODE, AML_ENTIRE_RANGE,
                     0x0000, 0x0000, 0x0CF7, 0x0000, 0x0CF8));
 
-    crs_replace_with_free_ranges(io_ranges, 0x0D00, 0xFFFF);
-    for (i = 0; i < io_ranges->len; i++) {
-        entry = g_ptr_array_index(io_ranges, i);
+    crs_replace_with_free_ranges(crs_range_set.io_ranges, 0x0D00, 0xFFFF);
+    for (i = 0; i < crs_range_set.io_ranges->len; i++) {
+        entry = g_ptr_array_index(crs_range_set.io_ranges, i);
         aml_append(crs,
             aml_word_io(AML_MIN_FIXED, AML_MAX_FIXED,
                         AML_POS_DECODE, AML_ENTIRE_RANGE,
@@ -2150,9 +2170,10 @@ build_dsdt(GArray *table_data, GArray *linker,
                          AML_CACHEABLE, AML_READ_WRITE,
                          0, 0x000A0000, 0x000BFFFF, 0, 0x00020000));
 
-    crs_replace_with_free_ranges(mem_ranges, pci->w32.begin, pci->w32.end - 1);
-    for (i = 0; i < mem_ranges->len; i++) {
-        entry = g_ptr_array_index(mem_ranges, i);
+    crs_replace_with_free_ranges(crs_range_set.mem_ranges,
+                                 pci->w32.begin, pci->w32.end - 1);
+    for (i = 0; i < crs_range_set. mem_ranges->len; i++) {
+        entry = g_ptr_array_index(crs_range_set.mem_ranges, i);
         aml_append(crs,
             aml_dword_memory(AML_POS_DECODE, AML_MIN_FIXED, AML_MAX_FIXED,
                              AML_NON_CACHEABLE, AML_READ_WRITE,
@@ -2187,8 +2208,7 @@ build_dsdt(GArray *table_data, GArray *linker,
     aml_append(dev, aml_name_decl("_CRS", crs));
     aml_append(scope, dev);
 
-    g_ptr_array_free(io_ranges, true);
-    g_ptr_array_free(mem_ranges, true);
+    crs_range_set_free(&crs_range_set);
 
     /* reserve PCIHP resources */
     if (pm->pcihp_io_len) {
