Instead of using sequential indices, use CRC32 of padding contents

Sequential indices are problematic for future updates, as updates in the
middle of the structure are common, and they will result in larger and
less readable diffs. Instead we can use the CRC32 of the padding
contents to name the field.

Author: zeux

generate.py

@@ -7,6 +7,7 @@
 import urllib
 import xml.etree.ElementTree as etree
 import urllib.request
+import zlib
 
 cmdversions = {
 	"vkCmdSetDiscardRectangleEnableEXT": 2,
@@ -157,15 +158,17 @@ def cdepends(key):
 	for key in block_keys:
 		blocks[key] = ''
 
-	devi = 0
+	devp = {}
 
 	for (group, cmdnames) in command_groups.items():
 		ifdef = '#if ' + group + '\n'
-		devt = 0
 
 		for key in block_keys:
 			blocks[key] += ifdef
 
+		devt = 0
+		devo = len(blocks['DEVICE_TABLE'])
+
 		for name in sorted(cmdnames):
 			cmd = commands[name]
 			type = cmd.findtext('param[1]/type')
@@ -192,9 +195,12 @@ def cdepends(key):
 			if blocks[key].endswith(ifdef):
 				blocks[key] = blocks[key][:-len(ifdef)]
 			elif key == 'DEVICE_TABLE':
-				devi += 1
+				devh = zlib.crc32(blocks[key][devo:].encode())
+				assert(devh not in devp)
+				devp[devh] = True
+
 				blocks[key] += '#else\n'
-				blocks[key] += '\tPFN_vkVoidFunction padding' + str(devi) + '[' + str(devt) + '];\n'
+				blocks[key] += f'\tPFN_vkVoidFunction padding_{devh:x}[{devt}];\n'
 				blocks[key] += '#endif /* ' + group + ' */\n'
 			else:
 				blocks[key] += '#endif /* ' + group + ' */\n'