[PATCH] D30451: [X86][AVX512] Adding new LLVM TableGen backend which generates the EVEX2VEX compressing tables.

[Ayman Musa via Phabricator via llvm-commits]

aymanmus marked an inline comment as done.
aymanmus added inline comments.


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Comment at: utils/TableGen/X86EVEX2VEXTablesEmitter.cpp:111
+
+      {"VPERMILPDZ128mi",     "VPERMILPDmi",     true},
+      {"VPERMILPDZ128ri",     "VPERMILPDri",     true},
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craig.topper wrote:
> What special about VPERMILPD that need to be manually added?
> 
> Same question for the BROADCASTs.
They do not accept on the W-bit.
VEX version have WIG0 while EVEX version have WIG1.


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Comment at: utils/TableGen/X86EVEX2VEXTablesEmitter.cpp:316
+    // (instructions with the same opcode) using function object IsMatch.
+    auto Match = llvm::find_if(VEXInsts[Opcode], IsMatch(EVEXInst));
+    if (Match != VEXInsts[Opcode].end()) {
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craig.topper wrote:
> How does this handle the MAX and MAXC instructions both having the same opcode information?
As I said in the other patch, in this stage of the compiler, there is no difference between MAX and MAXC, so the first to match is picked.


https://reviews.llvm.org/D30451