Disable LLVM's vectorizers by default (#9642)

compiler/src/iree/compiler/Dialect/HAL/Target/LLVM/LLVMTargetOptions.cpp

diff --git a/compiler/src/iree/compiler/Dialect/HAL/Target/LLVM/LLVMTargetOptions.cpp b/compiler/src/iree/compiler/Dialect/HAL/Target/LLVM/LLVMTargetOptions.cpp
index 3ca759c..56766e4 100644
--- a/compiler/src/iree/compiler/Dialect/HAL/Target/LLVM/LLVMTargetOptions.cpp
+++ b/compiler/src/iree/compiler/Dialect/HAL/Target/LLVM/LLVMTargetOptions.cpp
@@ -41,11 +41,11 @@
 
     // LLVM loop optimization options.
     targetOptions.pipelineTuningOptions.LoopInterleaving = true;
-    targetOptions.pipelineTuningOptions.LoopVectorization = true;
+    targetOptions.pipelineTuningOptions.LoopVectorization = false;
     targetOptions.pipelineTuningOptions.LoopUnrolling = true;
 
     // LLVM SLP Auto vectorizer.
-    targetOptions.pipelineTuningOptions.SLPVectorization = true;
+    targetOptions.pipelineTuningOptions.SLPVectorization = false;
 
     // LLVM -O3.
     // TODO(benvanik): add an option for this.
@@ -81,7 +81,7 @@
       "iree-llvm-loop-interleaving", llvm::cl::init(false),
       llvm::cl::desc("Enable LLVM loop interleaving opt"));
   static llvm::cl::opt<bool> llvmLoopVectorization(
-      "iree-llvm-loop-vectorization", llvm::cl::init(true),
+      "iree-llvm-loop-vectorization", llvm::cl::init(false),
       llvm::cl::desc("Enable LLVM loop vectorization opt"));
   static llvm::cl::opt<bool> llvmLoopUnrolling(
       "iree-llvm-loop-unrolling", llvm::cl::init(true),