Revert "Disable LLVM patches: 1-stripPointerCastsAndOffsets-should-not 2_2-completely-turn-off-code-sinking-in-InstructionCombining"

This reverts commit b259eb8.

Change-Id: Ia2a23cd90c3481c8e09c10cedb4fddb2fac3c36e

Author: paigeale

releases/4.0.0/patches_external/1-stripPointerCastsAndOffsets-should-not.patch

@@ -0,0 +1,18 @@
+#    Description                  : stripPointerCastsAndOffsets should not process across AddrSpaceCast
+
+
+diff -Naur --strip-trailing-cr a/lib/IR/Value.cpp b/lib/IR/Value.cpp
+--- a/lib/IR/Value.cpp	2016-12-07 13:47:32.000000000 -0800
++++ b/lib/IR/Value.cpp	2018-03-12 11:25:42.752625100 -0700
+@@ -466,6 +466,11 @@
+       V = GEP->getPointerOperand();
+     } else if (Operator::getOpcode(V) == Instruction::BitCast ||
+                Operator::getOpcode(V) == Instruction::AddrSpaceCast) {
++      // Do not process across AddrSpaceCast, since its result could
++      // be a nullptr depending on the meaning of src and dest addrspace.
++      if (Operator::getOpcode(V) == Instruction::AddrSpaceCast) {
++         return V;
++      }
+       V = cast<Operator>(V)->getOperand(0);
+     } else if (GlobalAlias *GA = dyn_cast<GlobalAlias>(V)) {
+       if (StripKind == PSK_ZeroIndices || GA->isInterposable())

releases/4.0.0/patches_external/2_2-completely-turn-off-code-sinking-in-InstructionCombining.patch

@@ -0,0 +1,17 @@
+#    Description                : completely turn off code-sinking in InstructionCombining.
+
+
+diff -Naur --strip-trailing-cr a/lib/Transforms/InstCombine/InstructionCombining.cpp b/lib/Transforms/InstCombine/InstructionCombining.cpp
+--- a/lib/Transforms/InstCombine/InstructionCombining.cpp	2017-10-23 09:48:44.308224955 -0400
++++ b/lib/Transforms/InstCombine/InstructionCombining.cpp	2017-10-23 09:49:06.404224089 -0400
+@@ -2871,7 +2871,9 @@
+     }
+ 
+     // See if we can trivially sink this instruction to a successor basic block.
+-    if (I->hasOneUse()) {
++    /*** turn off code-sinking ***/
++    /***  if (I->hasOneUse()) { ***/
++    if (0) {
+       BasicBlock *BB = I->getParent();
+       Instruction *UserInst = cast<Instruction>(*I->user_begin());
+       BasicBlock *UserParent;