Changeset 108945 in vbox

Timestamp:

Apr 11, 2025 9:18:48 AM (9 days ago)

Author:

vboxsync

svn:sync-xref-src-repo-rev:

168456

Message:

VMM/IEM: Check that the encodeset stuff covers the whole 32 bits of the instruction. Optimized parent instruction conditions referring to fixed instruction encoding values. jiraref:VBP-1598

File:

• trunk/src/VBox/VMM/VMMAll/target-armv8/bsd-spec-analyze.py (modified) (9 diffs)

trunk/src/VBox/VMM/VMMAll/target-armv8/bsd-spec-analyze.py

@@ -1213 +1213 @@
 
 
-def parseInstructions(oParent, aoJson, ddAsmRules):
+def parseInstructions(oInstrSet, oParent, aoJson, ddAsmRules):
     for oJson in aoJson:
         sType = oJson['_type'];
         if sType == 'Instruction.InstructionSet':
             if oParent: raise Exception("InstructionSet shouldn't have a parent!");
+            assert not oInstrSet;
             oInstrSet = ArmInstructionSet.fromJson(oJson);
             assert oInstrSet.sName not in g_dArmInstructionSets;
@@ -1223 +1224 @@
             g_aoArmInstructionSets.append(oInstrSet);
 
-            parseInstructions(oInstrSet, oJson['children'], ddAsmRules);
+            parseInstructions(oInstrSet, oInstrSet, oJson['children'], ddAsmRules);
 
         elif sType == 'Instruction.InstructionGroup':
@@ -1240 +1241 @@
             oParent.aoGroups.append(oInstrGroup);
 
-            parseInstructions(oInstrGroup, oJson['children'], ddAsmRules);
+            parseInstructions(oInstrSet, oInstrGroup, oJson['children'], ddAsmRules);
 
         elif sType == "Instruction.Instruction":
@@ -1250 +1251 @@
             sInstrNm = oJson['name'];
 
+            oCondition = ArmAstBase.fromJson(oJson['condition']);
+
             (aoFields, fFields) = ArmEncodesetField.encodesetFromJson(oJson['encoding']);
-            oCondition          = ArmAstBase.fromJson(oJson['condition']);
-
             for oUp in oParent.getUpIterator():
                 if oUp.fFields & ~fFields:
@@ -1258 +1259 @@
                 if not oUp.oCondition.isBoolAndTrue():
                     oCondition = ArmAstBinaryOp(oCondition, '&&', oUp.oCondition.clone());
+            if fFields != (1 << oInstrSet.cBitsWidth) - 1:
+                raise Exception('Instruction %s has an incomplete encodingset: fFields=%#010x (missing %#010x)'
+                                % (sInstrNm, fFields, fFields ^ ((1 << oInstrSet.cBitsWidth) - 1),))
 
             #sCondBefore = oCondition.toString();
             #print('debug transfer: %s: org:  %s' % (sInstrNm, sCondBefore));
-            ## @todo fFields isn't updated here!
             (oCondition, fMod) = transferConditionsToEncoding(oCondition, aoFields, collections.defaultdict(list), sInstrNm);
             #if fMod:
@@ -1482 +1485 @@
     global g_oArmInstructionVerInfo;
     g_oArmInstructionVerInfo = dRawInstructions['_meta']['version'];
-    parseInstructions([], dRawInstructions['instructions'], dRawInstructions['assembly_rules']);
+    parseInstructions(None, None, dRawInstructions['instructions'], dRawInstructions['assembly_rules']);
 
     # Sort the instruction array by name.
@@ -2242 +2245 @@
                     return (sName, oField.cBitsWidth);
                 # Look for the field in groups and sets and generate a name that extracts it from uOpcode:
-                ## @todo eliminate conditions checks from the parent on parent fields that are fixed in the given instr.
                 for oParent in oInstr.oParent.getUpIterator():
                     oField = oParent.getFieldByName(sName, False);
                     if oField:
+                        fFieldOpMask = oField.getShiftedMask();
+                        if (oInstr.fFixedMask & fFieldOpMask) == fFieldOpMask:
+                            return ('%#x /*%s@%u*/'
+                                    % ((oInstr.fFixedValue & fFieldOpMask) >> oField.iFirstBit, sName, oField.iFirstBit),
+                                    oField.cBitsWidth);
                         return ('((uOpcode >> %u) & %#x)' % (oField.iFirstBit, oField.getMask()), oField.cBitsWidth);
                 raise Exception('Field %s was not found for instruction %s' % (sName, oInstr.sName,));
@@ -2259 +2266 @@
                     sCpumFeature = g_dSpecFeatToCpumFeat.get(sFeatureNm, None);
                     if sCpumFeature is None:
-                        print('warning: IsFeatureImplemented parameter not known: %s (see g_dSpecFeatToCpumFeat)' % (sFeatureNm));
-                        #raise Exception('IsFeatureImplemented parameter not known: %s (see g_dSpecFeatToCpumFeat)'
-                        #                % (sFeatureNm));
+                        raise Exception('Unknown IsFeatureImplemented parameter: %s (see g_dSpecFeatToCpumFeat)' % (sFeatureNm));
                     if not isinstance(sCpumFeature, str):
                         return 'false /** @todo IEM_GET_GUEST_CPU_FEATURES(pVCpu)->%s*/' % (sFeatureNm,);
@@ -2326 +2331 @@
                 '%s    LogFlow(("%%010x: %s%s\\n",%s));' % (sIndent, sCName, sLogFmt, ', '.join(['uOpcode',] + asArgs),),
                 '#ifdef IEM_INSTR_IMPL_%s__%s' % (sInstrSet, sCName,),
-                '%s    IEM_INSTR_IMPL_%s__%s(%s);' % (sInstrSet, sIndent, sCName, ', '.join(asArgs),),
+                '%s    IEM_INSTR_IMPL_%s__%s(%s);' % (sIndent, sInstrSet, sCName, ', '.join(asArgs),),
                 '#else',
                 '%s    RT_NOREF(%s);' % (sIndent, ', '.join(asArgs + ['pVCpu', 'uOpcode',]),),