[X86] Change std::sort to llvm::sort in response to r327219

[mgrang]

Summary

r327219 added wrappers to std::sort which randomly shuffle the container before sorting.
This will help in uncovering non-determinism caused due to undefined sorting
order of objects having the same key.

To make use of that infrastructure we need to invoke llvm::sort instead of std::sort.

Note: This patch is one of a series of patches to replace *all* std::sort to llvm::sort.
Refer the comments section in D44363 for a list of all the required patches.

[craig.topper]

lib/Target/X86/X86ISelLowering.cpp

11677

I wonder if these would be better as array_pod_sort

[chandlerc]

LGTM

[mgrang]

Changed std::sort to array_pod_sort for containers with pod keys, and llvm::sort for container with StringRef key.

[mgrang]

@craig.topper I have changed the sort functions for pod containers to array_pod_sort. Could you please review?

[craig.topper]

lib/Target/X86/X86ISelLowering.cpp

38877

StringRef should be pod so why did this need to change?

[mgrang]

lib/Target/X86/X86ISelLowering.cpp

38877

Seems to have been an oversight in replacing these. I have fixed it in my latest patch. Thanks!

[craig.topper]

LGTM

lib/Target/X86/X86ISelLowering.cpp

if (isUndefOrInRange(HiMask, 4, 8) &&
     for (int i = 0; i != 4; ++i)
       HiMask[i] = (HiMask[i] < 0 ? HiMask[i] : (HiMask[i] - 4));
     return DAG.getNode(X86ISD::PSHUFHW, DL, VT, V,
                        getV4X86ShuffleImm8ForMask(HiMask, DL, DAG));
   }
 
   SmallVector<int, 4> LoInputs;
   copy_if(LoMask, std::back_inserter(LoInputs), [](int M) { return M >= 0; });
-  std::sort(LoInputs.begin(), LoInputs.end());
+  array_pod_sort(LoInputs.begin(), LoInputs.end());
   LoInputs.erase(std::unique(LoInputs.begin(), LoInputs.end()), LoInputs.end());
   SmallVector<int, 4> HiInputs;
   copy_if(HiMask, std::back_inserter(HiInputs), [](int M) { return M >= 0; });
-  std::sort(HiInputs.begin(), HiInputs.end());
+  array_pod_sort(HiInputs.begin(), HiInputs.end());
   HiInputs.erase(std::unique(HiInputs.begin(), HiInputs.end()), HiInputs.end());
   int NumLToL =
       std::lower_bound(LoInputs.begin(), LoInputs.end(), 4) - LoInputs.begin();
   int NumHToL = LoInputs.size() - NumLToL;
   int NumLToH =
       std::lower_bound(HiInputs.begin(), HiInputs.end(), 4) - HiInputs.begin();
   int NumHToH = HiInputs.size() - NumLToH;
   MutableArrayRef<int> LToLInputs(LoInputs.data(), NumLToL);
auto canWidenViaDuplication = [](ArrayRef<int> Mask) {
       return true;
     };
     auto tryToWidenViaDuplication = [&]() -> SDValue {
       if (!canWidenViaDuplication(Mask))
         return SDValue();
       SmallVector<int, 4> LoInputs;
       copy_if(Mask, std::back_inserter(LoInputs),
               [](int M) { return M >= 0 && M < 8; });
-      std::sort(LoInputs.begin(), LoInputs.end());
+      array_pod_sort(LoInputs.begin(), LoInputs.end());
       LoInputs.erase(std::unique(LoInputs.begin(), LoInputs.end()),
                      LoInputs.end());
       SmallVector<int, 4> HiInputs;
       copy_if(Mask, std::back_inserter(HiInputs), [](int M) { return M >= 8; });
-      std::sort(HiInputs.begin(), HiInputs.end());
+      array_pod_sort(HiInputs.begin(), HiInputs.end());
       HiInputs.erase(std::unique(HiInputs.begin(), HiInputs.end()),
                      HiInputs.end());
 
       bool TargetLo = LoInputs.size() >= HiInputs.size();
       ArrayRef<int> InPlaceInputs = TargetLo ? LoInputs : HiInputs;
       ArrayRef<int> MovingInputs = TargetLo ? HiInputs : LoInputs;
 
       int PreDupI16Shuffle[] = {-1, -1, -1, -1, -1, -1, -1, -1};
case 1:
     // rorw $$8, ${0:w}  -->  llvm.bswap.i16
     if (CI->getType()->isIntegerTy(16) &&
         IA->getConstraintString().compare(0, 5, "=r,0,") == 0 &&
         (matchAsm(AsmPieces[0], {"rorw", "$$8,", "${0:w}"}) ||
          matchAsm(AsmPieces[0], {"rolw", "$$8,", "${0:w}"}))) {
       AsmPieces.clear();
       StringRef ConstraintsStr = IA->getConstraintString();
       SplitString(StringRef(ConstraintsStr).substr(5), AsmPieces, ",");
-      array_pod_sort(AsmPieces.begin(), AsmPieces.end());
+      llvm::sort(AsmPieces.begin(), AsmPieces.end());
       if (clobbersFlagRegisters(AsmPieces))
         return IntrinsicLowering::LowerToByteSwap(CI);
     }
     break;
   case 3:
     if (CI->getType()->isIntegerTy(32) &&
         IA->getConstraintString().compare(0, 5, "=r,0,") == 0 &&
         matchAsm(AsmPieces[0], {"rorw", "$$8,", "${0:w}"}) &&
         matchAsm(AsmPieces[1], {"rorl", "$$16,", "$0"}) &&
         matchAsm(AsmPieces[2], {"rorw", "$$8,", "${0:w}"})) {
       AsmPieces.clear();
       StringRef ConstraintsStr = IA->getConstraintString();
       SplitString(StringRef(ConstraintsStr).substr(5), AsmPieces, ",");
-      array_pod_sort(AsmPieces.begin(), AsmPieces.end());
+      llvm::sort(AsmPieces.begin(), AsmPieces.end());
       if (clobbersFlagRegisters(AsmPieces))
         return IntrinsicLowering::LowerToByteSwap(CI);
     }
 
     if (CI->getType()->isIntegerTy(64)) {
       InlineAsm::ConstraintInfoVector Constraints = IA->ParseConstraints();
       if (Constraints.size() >= 2 &&
           Constraints[0].Codes.size() == 1 && Constraints[0].Codes[0] == "A" &&