Changeset 108876 in vbox for trunk/src/VBox/VMM/VMMAll/target-armv8/bsd-spec-analyze.py

Timestamp:

Apr 8, 2025 1:04:50 AM (2 weeks ago)

Author:

vboxsync

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

168326

Message:

VMM/IEM: Working on the ARM bsd/opensource spec reader & decoder generator. Work in progress. Basic construction algo should be there now. jiraref:VBP-1598

File:

• trunk/src/VBox/VMM/VMMAll/target-armv8/bsd-spec-analyze.py (modified) (8 diffs)

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

@@ -1144 +1144 @@
         cInstructions = len(self.aoInstructions)
         if cInstructions <= 4:
-            #assert len(self.dChildren) == 0;
+            assert not self.dChildren;
             uCost = 0;
             # Special case: 1 instruction - leaf.
@@ -1157 +1157 @@
             else:
                 self.fChildMask = DecoderNode.kChildMaskMultipleOpcodeValueIfs;
-                for i, oInstr in enumerate(self.aoInstructions):
-                    self.dChildren[i] = DecoderNode([oInstr], oInstr.fFixedMask, oInstr.fFixedMask);
                 uCost = 32 * cInstructions * 2;                                         # 32 = kCostMultipleOpcodeValueIfs
-            return uCost #<< uDepth;
+            return uCost;
 
         #
@@ -1241 +1239 @@
                     uCostTmp    = 256;                                                  # 256 = kCostIndirectCall
                     uCostTmp   += (len(aaiMaskToIdxAlgo) - 1) * 2;                      #   2 = kCostPerExtraIndexStep
-                    #uCostTmp  <<= uDepth;   # Make the cost exponentially higher with depth. (?)
                     if uCostTmp >= uCostBest:
                         #if uDepth <= 2:
@@ -1275 +1272 @@
                     cNominalFill = 1 << (cMaskBits - 1); # 50% full or better is great.
                     if len(daoTmp) < cNominalFill:
-                        uCostTmp += ((cNominalFill - len(daoTmp)) * 2) #<< uDepth;  # 2 = kCostUnusedTabEntry
+                        uCostTmp += ((cNominalFill - len(daoTmp)) * 2);                 # 2 = kCostUnusedTabEntry
                         if uCostTmp >= uCostBest:
                             #if uDepth <= 2:
@@ -1502 +1499 @@
         Handles a leaf node.
         """
-        assert not oNode.dChildren;
+        assert not oNode.dChildren, \
+               'fChildMask=%#x dChildren=%s aoInstr=%s' % (oNode.fChildMask, oNode.dChildren, oNode.aoInstructions,);
 
         asLines = [
@@ -1527 +1525 @@
         Recursively generates the decoder code.
         """
-        assert oNode.fChildMask != 0 and oNode.fChildMask < (1 << 24), \
+        assert oNode.fChildMask != 0 and oNode.fChildMask not in (0x7fffffff, 0xffffffff, 0x4fffffff), \
             'fChildMask=%s #dChildren=%s aoInstr=%s' % (oNode.fChildMask, len(oNode.dChildren), oNode.aoInstructions,);
         asLines = [];
@@ -1533 +1531 @@
         # First recurse.
         for oChildNode in oNode.dChildren.values():
-            if oChildNode.fChildMask == DecoderNode.kChildMaskMultipleOpcodeValueIfs:
+            if oChildNode.dChildren:
+                asLines += self.generateDecoderCode(oChildNode, uDepth + 1);
+            elif oChildNode.fChildMask == DecoderNode.kChildMaskMultipleOpcodeValueIfs:
+                assert len(oChildNode.aoInstructions) > 1;
                 asLines += self.generateDecoderCodeMultiIfFunc(oChildNode, uDepth + 1);
-            elif oChildNode.fChildMask != DecoderNode.kChildMaskOpcodeValueIf:
-                assert oChildNode.dChildren;
-                asLines += self.generateDecoderCode(oChildNode, uDepth + 1);
             else:
-                assert not oChildNode.dChildren;
+                assert len(oChildNode.aoInstructions) == 1;
+                assert oChildNode.fChildMask in [DecoderNode.kChildMaskOpcodeValueIf, 0];
 
         # Generate the function.
@@ -1570 +1569 @@
         assert aaiAlgo, 'fChildMask=%s #children=%s instrs=%s' % (oNode.fChildMask, len(oNode.dChildren), oNode.aoInstructions,);
         asIdx = [
-            '    uintptr_t const idx = ((uOpcode >> %2u) & %#010x) /* bit %u L %u -> 0 */'
+            '    uintptr_t const idx = ((uOpcode >> %2u) & %#010x) /* bit %2u L %u -> 0 */'
             % (aaiAlgo[0][0], aaiAlgo[0][2], aaiAlgo[0][0], aaiAlgo[0][2].bit_count(), ),
         ];
         for iSrcBit, iDstBit, fMask in aaiAlgo[1:]:
-            asIdx.append('                        | ((uOpcode >> %2u) & %#010x) /* bit %u L %u -> %u */'
+            asIdx.append('                        | ((uOpcode >> %2u) & %#010x) /* bit %2u L %u -> %u */'
                          % (iSrcBit - iDstBit, fMask << iDstBit, iSrcBit, fMask.bit_count(), iDstBit));
         asIdx[-1] += ';';