[PATCH] D37320: [X86] Teach fastisel to handle zext/sext i8->i16 and sext i1->i8/i16/i32/i64

[Guy Blank via Phabricator via llvm-commits]

guyblank added inline comments.


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Comment at: lib/Target/X86/X86FastISel.cpp:1595
+                                          /*TODO: Kill=*/false);
+    if (ResultReg == 0)
+      return false;
----------------
should this check ZExtReg and not ResultReg?


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Comment at: lib/Target/X86/X86FastISel.cpp:1607
+  if (DstVT == MVT::i16) {
+    // i8->i16 doesn't exist in the autogenerated isel table. Need to zero
+    // extend to 32-bits and then extract down to 16-bits.
----------------
Need to zero extend -> Need to sign extend


https://reviews.llvm.org/D37320