diff --git a/clang/lib/CodeGen/BackendUtil.cpp b/clang/lib/CodeGen/BackendUtil.cpp
--- a/clang/lib/CodeGen/BackendUtil.cpp
+++ b/clang/lib/CodeGen/BackendUtil.cpp
@@ -1437,6 +1437,12 @@
   Conf.OptLevel = CGOpts.OptimizationLevel;
   initTargetOptions(Conf.Options, CGOpts, TOpts, LOpts, HeaderOpts);
   Conf.SampleProfile = std::move(SampleProfile);
+  Conf.PTO.LoopUnrolling = CGOpts.UnrollLoops;
+  // For historical reasons, loop interleaving is set to mirror setting for loop
+  // unrolling.
+  Conf.PTO.LoopInterleaving = CGOpts.UnrollLoops;
+  Conf.PTO.LoopVectorization = CGOpts.VectorizeLoop;
+  Conf.PTO.SLPVectorization = CGOpts.VectorizeSLP;
 
   // Context sensitive profile.
   if (CGOpts.hasProfileCSIRInstr()) {
diff --git a/clang/test/CodeGen/thinlto-slp-vectorize-pm.c b/clang/test/CodeGen/thinlto-slp-vectorize-pm.c
new file mode 100644
--- /dev/null
+++ b/clang/test/CodeGen/thinlto-slp-vectorize-pm.c
@@ -0,0 +1,50 @@
+// REQUIRES: x86-registered-target
+// RUN: %clang_cc1 -o %t.o -flto=thin -fexperimental-new-pass-manager -triple x86_64-unknown-linux-gnu -emit-llvm-bc %s
+// RUN: llvm-lto -thinlto -o %t %t.o
+
+// Test to ensure the slp vectorize codegen option is passed down to the
+// ThinLTO backend. -vectorize-slp is a cc1 option and will be added
+// automatically when O2/O3/Os/Oz is available for clang. Once -vectorize-slp
+// is enabled, "-mllvm -vectorize-slp=false" won't disable slp vectorization
+// currently. "-mllvm -vectorize-slp=false" is added here in the test to
+// ensure the slp vectorization is executed because the -vectorize-slp cc1
+// flag is passed down, not because "-mllvm -vectorize-slp" is enabled
+// by default.
+//
+// RUN: %clang_cc1 -triple x86_64-unknown-linux-gnu -emit-obj -O2 -vectorize-slp -mllvm -vectorize-slp=false -o %t2.o -x ir %t.o -fthinlto-index=%t.thinlto.bc -fdebug-pass-manager -fexperimental-new-pass-manager 2>&1 | FileCheck %s --check-prefix=O2-SLP
+// RUN: %clang_cc1 -triple x86_64-unknown-linux-gnu -emit-obj -O0 -vectorize-slp -mllvm -vectorize-slp=false -o %t2.o -x ir %t.o -fthinlto-index=%t.thinlto.bc -fdebug-pass-manager -fexperimental-new-pass-manager 2>&1 | FileCheck %s --check-prefix=O0-SLP
+// O2-SLP: Running pass: SLPVectorizerPass
+// O0-SLP-NOT: Running pass: SLPVectorizerPass
+
+// Test to ensure the loop vectorize codegen option is passed down to the
+// ThinLTO backend. -vectorize-loops is a cc1 option and will be added
+// automatically when O2/O3/Os is available for clang. Once -vectorize-loops is
+// enabled, "-mllvm -vectorize-loops=false" won't disable loop vectorization
+// currently. "-mllvm -vectorize-loops=false" is added here in the test to
+// ensure the loop vectorization is executed because the -vectorize-loops cc1
+// flag is passed down, not because "-mllvm -vectorize-loops" is enabled
+// by default.
+//
+// RUN: %clang_cc1 -triple x86_64-unknown-linux-gnu -emit-obj -O2 -vectorize-loops -mllvm -vectorize-loops=false -mllvm -force-vector-width=2 -mllvm -force-vector-interleave=1 -emit-llvm -o - -x ir %t.o -fthinlto-index=%t.thinlto.bc -fexperimental-new-pass-manager 2>&1 | FileCheck %s --check-prefix=O2-LPV
+// RUN: %clang_cc1 -triple x86_64-unknown-linux-gnu -emit-obj -O0 -vectorize-loops -mllvm -vectorize-loops=false -mllvm -force-vector-width=2 -mllvm -force-vector-interleave=1 -emit-llvm -o - -x ir %t.o -fthinlto-index=%t.thinlto.bc -fexperimental-new-pass-manager 2>&1 | FileCheck %s --check-prefix=O0-LPV
+// O2-LPV: = !{!"llvm.loop.isvectorized", i32 1}
+// O0-LPV-NOT: = !{!"llvm.loop.isvectorized", i32 1}
+
+// Test to ensure the loop interleave codegen option is passed down to the
+// ThinLTO backend. The internal loop interleave codegen option will be
+// enabled automatically when O2/O3 is available for clang. Once the loop
+// interleave option is enabled, "-mllvm -interleave-loops=false" won't disable
+// the interleave. currently. "-mllvm -interleave-loops=false" is added here
+// in the test to ensure the loop interleave is executed because the interleave
+// codegen flag is passed down, not because "-mllvm -interleave-loops" is
+// enabled by default.
+//
+// RUN: %clang_cc1 -triple x86_64-unknown-linux-gnu -emit-obj -O2 -vectorize-loops -mllvm -interleave-loops=false -mllvm -force-vector-width=1 -mllvm -force-vector-interleave=2 -emit-llvm -o - -x ir %t.o -fthinlto-index=%t.thinlto.bc -fexperimental-new-pass-manager 2>&1 | FileCheck %s --check-prefix=O2-InterLeave
+// RUN: %clang_cc1 -triple x86_64-unknown-linux-gnu -emit-obj -O0 -vectorize-loops -mllvm -interleave-loops=false -mllvm -force-vector-width=1 -mllvm -force-vector-interleave=2 -emit-llvm -o - -x ir %t.o -fthinlto-index=%t.thinlto.bc -fexperimental-new-pass-manager 2>&1 | FileCheck %s --check-prefix=O0-InterLeave
+// O2-InterLeave: = !{!"llvm.loop.isvectorized", i32 1}
+// O0-InterLeave-NOT: = !{!"llvm.loop.isvectorized", i32 1}
+
+void foo(double *a) {
+  for (int i = 0; i < 1000; i++)
+    a[i] = 10;
+}
diff --git a/lld/COFF/CMakeLists.txt b/lld/COFF/CMakeLists.txt
--- a/lld/COFF/CMakeLists.txt
+++ b/lld/COFF/CMakeLists.txt
@@ -37,6 +37,7 @@
   MC
   Object
   Option
+  Passes
   Support
   WindowsManifest
 
diff --git a/lld/ELF/CMakeLists.txt b/lld/ELF/CMakeLists.txt
--- a/lld/ELF/CMakeLists.txt
+++ b/lld/ELF/CMakeLists.txt
@@ -57,6 +57,7 @@
   MC
   Object
   Option
+  Passes
   Support
 
   LINK_LIBS
diff --git a/lld/ELF/LTO.cpp b/lld/ELF/LTO.cpp
--- a/lld/ELF/LTO.cpp
+++ b/lld/ELF/LTO.cpp
@@ -93,6 +93,9 @@
   c.MAttrs = getMAttrs();
   c.CGOptLevel = args::getCGOptLevel(config->ltoo);
 
+  c.PTO.LoopVectorization = c.OptLevel > 1;
+  c.PTO.SLPVectorization = c.OptLevel > 1;
+
   // Set up a custom pipeline if we've been asked to.
   c.OptPipeline = config->ltoNewPmPasses;
   c.AAPipeline = config->ltoAAPipeline;
diff --git a/lld/test/ELF/lto/slp-vectorize-pm.ll b/lld/test/ELF/lto/slp-vectorize-pm.ll
new file mode 100644
--- /dev/null
+++ b/lld/test/ELF/lto/slp-vectorize-pm.ll
@@ -0,0 +1,48 @@
+; REQUIRES: x86
+; RUN: opt -module-summary %s -o %t.o
+
+; Test SLP and Loop Vectorization are enabled by default at O2 and O3.
+; RUN: ld.lld --plugin-opt=new-pass-manager --plugin-opt=debug-pass-manager --plugin-opt=O0 --plugin-opt=save-temps -shared -o %t1.o %t.o 2>&1 | FileCheck %s --check-prefix=CHECK-O0-SLP
+; RUN: llvm-dis %t.o.4.opt.bc -o - | FileCheck %s --check-prefix=CHECK-O0-LPV
+
+; RUN: ld.lld --plugin-opt=new-pass-manager --plugin-opt=debug-pass-manager --plugin-opt=O1 --plugin-opt=save-temps -shared -o %t2.o %t.o 2>&1 | FileCheck %s --check-prefix=CHECK-O1-SLP
+; RUN: llvm-dis %t.o.4.opt.bc -o - | FileCheck %s --check-prefix=CHECK-O1-LPV
+
+; RUN: ld.lld --plugin-opt=new-pass-manager --plugin-opt=debug-pass-manager --plugin-opt=O2 --plugin-opt=save-temps -shared -o %t3.o %t.o 2>&1 | FileCheck %s --check-prefix=CHECK-O2-SLP
+; RUN: llvm-dis %t.o.4.opt.bc -o - | FileCheck %s --check-prefix=CHECK-O2-LPV
+
+; RUN: ld.lld --plugin-opt=new-pass-manager --plugin-opt=debug-pass-manager --plugin-opt=O3 --plugin-opt=save-temps -shared -o %t4.o %t.o 2>&1 | FileCheck %s --check-prefix=CHECK-O3-SLP
+; RUN: llvm-dis %t.o.4.opt.bc -o - | FileCheck %s --check-prefix=CHECK-O3-LPV
+
+; CHECK-O0-SLP-NOT: Running pass: SLPVectorizerPass
+; CHECK-O1-SLP-NOT: Running pass: SLPVectorizerPass
+; CHECK-O2-SLP: Running pass: SLPVectorizerPass
+; CHECK-O3-SLP: Running pass: SLPVectorizerPass
+; CHECK-O0-LPV-NOT: = !{!"llvm.loop.isvectorized", i32 1}
+; CHECK-O1-LPV-NOT: = !{!"llvm.loop.isvectorized", i32 1}
+; CHECK-O2-LPV: = !{!"llvm.loop.isvectorized", i32 1}
+; CHECK-O3-LPV: = !{!"llvm.loop.isvectorized", i32 1}
+
+target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+define i32 @foo(i32* %a) {
+entry:
+  br label %for.body
+
+for.body:
+  %indvars.iv = phi i64 [ 0, %entry ], [ %indvars.iv.next, %for.body ]
+  %red.05 = phi i32 [ 0, %entry ], [ %add, %for.body ]
+  %arrayidx = getelementptr inbounds i32, i32* %a, i64 %indvars.iv
+  %0 = load i32, i32* %arrayidx, align 4
+  %add = add nsw i32 %0, %red.05
+  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
+  %exitcond = icmp eq i64 %indvars.iv.next, 255
+  br i1 %exitcond, label %for.end, label %for.body, !llvm.loop !0
+
+for.end:
+  ret i32 %add
+}
+
+!0 = distinct !{!0, !1}
+!1 = !{!"llvm.loop.unroll.disable", i1 true}
diff --git a/lld/wasm/CMakeLists.txt b/lld/wasm/CMakeLists.txt
--- a/lld/wasm/CMakeLists.txt
+++ b/lld/wasm/CMakeLists.txt
@@ -29,6 +29,7 @@
   MC
   Object
   Option
+  Passes
   Support
 
   LINK_LIBS
diff --git a/llvm/include/llvm/LTO/Config.h b/llvm/include/llvm/LTO/Config.h
--- a/llvm/include/llvm/LTO/Config.h
+++ b/llvm/include/llvm/LTO/Config.h
@@ -18,6 +18,7 @@
 #include "llvm/IR/DiagnosticInfo.h"
 #include "llvm/IR/GlobalValue.h"
 #include "llvm/IR/LLVMContext.h"
+#include "llvm/Passes/PassBuilder.h"
 #include "llvm/Support/CodeGen.h"
 #include "llvm/Target/TargetOptions.h"
 
@@ -128,6 +129,9 @@
   /// with llvm-lto2.
   std::unique_ptr<raw_ostream> ResolutionFile;
 
+  /// Tunable parameters for passes in the default pipelines.
+  PipelineTuningOptions PTO;
+
   /// The following callbacks deal with tasks, which normally represent the
   /// entire optimization and code generation pipeline for what will become a
   /// single native object file. Each task has a unique identifier between 0 and
diff --git a/llvm/lib/LTO/LTOBackend.cpp b/llvm/lib/LTO/LTOBackend.cpp
--- a/llvm/lib/LTO/LTOBackend.cpp
+++ b/llvm/lib/LTO/LTOBackend.cpp
@@ -172,7 +172,7 @@
   PassInstrumentationCallbacks PIC;
   StandardInstrumentations SI;
   SI.registerCallbacks(PIC);
-  PassBuilder PB(TM, PipelineTuningOptions(),PGOOpt, &PIC);
+  PassBuilder PB(TM, Conf.PTO, PGOOpt, &PIC);
   AAManager AA;
 
   // Parse a custom AA pipeline if asked to.
diff --git a/llvm/lib/Passes/PassBuilder.cpp b/llvm/lib/Passes/PassBuilder.cpp
--- a/llvm/lib/Passes/PassBuilder.cpp
+++ b/llvm/lib/Passes/PassBuilder.cpp
@@ -1902,6 +1902,12 @@
       return Error::success();
     }
 
+    // This is consistent with old pass manager invoked via opt, but
+    // inconsistent with clang. Clang doesn't enable loop vectorization
+    // but does enable slp vectorization at Oz.
+    PTO.LoopVectorization = L > O1 && L < Oz;
+    PTO.SLPVectorization = L > O1 && L < Oz;
+
     if (Matches[1] == "default") {
       MPM.addPass(buildPerModuleDefaultPipeline(L, DebugLogging));
     } else if (Matches[1] == "thinlto-pre-link") {
diff --git a/llvm/test/Other/new-pm-defaults.ll b/llvm/test/Other/new-pm-defaults.ll
--- a/llvm/test/Other/new-pm-defaults.ll
+++ b/llvm/test/Other/new-pm-defaults.ll
@@ -251,6 +251,9 @@
 ; CHECK-O-NEXT: Running analysis: LoopAccessAnalysis
 ; CHECK-O-NEXT: Running pass: InstCombinePass
 ; CHECK-O-NEXT: Running pass: SimplifyCFGPass
+; CHECK-O2-NEXT: Running pass: SLPVectorizerPass
+; CHECK-O3-NEXT: Running pass: SLPVectorizerPass
+; CHECK-Os-NEXT: Running pass: SLPVectorizerPass
 ; CHECK-O-NEXT: Running pass: InstCombinePass
 ; CHECK-O-NEXT: Running pass: LoopUnrollPass
 ; CHECK-O-NEXT: Running pass: WarnMissedTransformationsPass
diff --git a/llvm/test/Other/new-pm-thinlto-defaults.ll b/llvm/test/Other/new-pm-thinlto-defaults.ll
--- a/llvm/test/Other/new-pm-thinlto-defaults.ll
+++ b/llvm/test/Other/new-pm-thinlto-defaults.ll
@@ -221,6 +221,9 @@
 ; CHECK-POSTLINK-O-NEXT: Running analysis: LoopAccessAnalysis
 ; CHECK-POSTLINK-O-NEXT: Running pass: InstCombinePass
 ; CHECK-POSTLINK-O-NEXT: Running pass: SimplifyCFGPass
+; CHECK-POSTLINK-O2-NEXT: Running pass: SLPVectorizerPass
+; CHECK-POSTLINK-O3-NEXT: Running pass: SLPVectorizerPass
+; CHECK-POSTLINK-Os-NEXT: Running pass: SLPVectorizerPass
 ; CHECK-POSTLINK-O-NEXT: Running pass: InstCombinePass
 ; CHECK-POSTLINK-O-NEXT: Running pass: LoopUnrollPass
 ; CHECK-POSTLINK-O-NEXT: Running pass: WarnMissedTransformationsPass
diff --git a/llvm/test/tools/gold/X86/slp-vectorize-pm.ll b/llvm/test/tools/gold/X86/slp-vectorize-pm.ll
new file mode 100644
--- /dev/null
+++ b/llvm/test/tools/gold/X86/slp-vectorize-pm.ll
@@ -0,0 +1,79 @@
+; RUN: opt -module-summary %s -o %t.o
+
+; Test SLP and Loop Vectorization are enabled by default at O2 and O3.
+; RUN: %gold -m elf_x86_64 -plugin %llvmshlibdir/LLVMgold%shlibext \
+; RUN:     --plugin-opt=thinlto \
+; RUN:     --plugin-opt=new-pass-manager \
+; RUN:     --plugin-opt=debug-pass-manager \
+; RUN:     --plugin-opt=cache-dir=%t.cache \
+; RUN:     --plugin-opt=O0 \
+; RUN:     --plugin-opt=save-temps \
+; RUN:     -shared \
+; RUN:     -o %t2.o %t.o 2>&1 | FileCheck %s --check-prefix=CHECK-O0-SLP
+; RUN: llvm-dis %t.o.4.opt.bc -o - | FileCheck %s --check-prefix=CHECK-O0-LPV
+
+; RUN: %gold -m elf_x86_64 -plugin %llvmshlibdir/LLVMgold%shlibext \
+; RUN:     --plugin-opt=thinlto \
+; RUN:     --plugin-opt=new-pass-manager \
+; RUN:     --plugin-opt=debug-pass-manager \
+; RUN:     --plugin-opt=cache-dir=%t.cache \
+; RUN:     --plugin-opt=O1 \
+; RUN:     --plugin-opt=save-temps \
+; RUN:     -shared \
+; RUN:     -o %t3.o %t.o 2>&1 | FileCheck %s --check-prefix=CHECK-O1-SLP
+; RUN: llvm-dis %t.o.4.opt.bc -o - | FileCheck %s --check-prefix=CHECK-O1-LPV
+
+; RUN: %gold -m elf_x86_64 -plugin %llvmshlibdir/LLVMgold%shlibext \
+; RUN:     --plugin-opt=thinlto \
+; RUN:     --plugin-opt=new-pass-manager \
+; RUN:     --plugin-opt=debug-pass-manager \
+; RUN:     --plugin-opt=cache-dir=%t.cache \
+; RUN:     --plugin-opt=O2 \
+; RUN:     --plugin-opt=save-temps \
+; RUN:     -shared \
+; RUN:     -o %t4.o %t.o 2>&1 | FileCheck %s --check-prefix=CHECK-O2-SLP
+; RUN: llvm-dis %t.o.4.opt.bc -o - | FileCheck %s --check-prefix=CHECK-O2-LPV
+
+; RUN: %gold -m elf_x86_64 -plugin %llvmshlibdir/LLVMgold%shlibext \
+; RUN:     --plugin-opt=thinlto \
+; RUN:     --plugin-opt=new-pass-manager \
+; RUN:     --plugin-opt=debug-pass-manager \
+; RUN:     --plugin-opt=cache-dir=%t.cache \
+; RUN:     --plugin-opt=O3 \
+; RUN:     --plugin-opt=save-temps \
+; RUN:     -shared \
+; RUN:     -o %t5.o %t.o 2>&1 | FileCheck %s --check-prefix=CHECK-O3-SLP
+; RUN: llvm-dis %t.o.4.opt.bc -o - | FileCheck %s --check-prefix=CHECK-O3-LPV
+
+; CHECK-O0-SLP-NOT: Running pass: SLPVectorizerPass
+; CHECK-O1-SLP-NOT: Running pass: SLPVectorizerPass
+; CHECK-O2-SLP: Running pass: SLPVectorizerPass
+; CHECK-O3-SLP: Running pass: SLPVectorizerPass
+; CHECK-O0-LPV-NOT: = !{!"llvm.loop.isvectorized", i32 1}
+; CHECK-O1-LPV-NOT: = !{!"llvm.loop.isvectorized", i32 1}
+; CHECK-O2-LPV: = !{!"llvm.loop.isvectorized", i32 1}
+; CHECK-O3-LPV: = !{!"llvm.loop.isvectorized", i32 1}
+
+target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+define i32 @foo(i32* %a) {
+entry:
+  br label %for.body
+
+for.body:
+  %indvars.iv = phi i64 [ 0, %entry ], [ %indvars.iv.next, %for.body ]
+  %red.05 = phi i32 [ 0, %entry ], [ %add, %for.body ]
+  %arrayidx = getelementptr inbounds i32, i32* %a, i64 %indvars.iv
+  %0 = load i32, i32* %arrayidx, align 4
+  %add = add nsw i32 %0, %red.05
+  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
+  %exitcond = icmp eq i64 %indvars.iv.next, 255
+  br i1 %exitcond, label %for.end, label %for.body, !llvm.loop !0
+
+for.end:
+  ret i32 %add
+}
+
+!0 = distinct !{!0, !1}
+!1 = !{!"llvm.loop.unroll.disable", i1 true}
diff --git a/llvm/test/tools/llvm-lto2/X86/slp-vectorize-pm.ll b/llvm/test/tools/llvm-lto2/X86/slp-vectorize-pm.ll
new file mode 100644
--- /dev/null
+++ b/llvm/test/tools/llvm-lto2/X86/slp-vectorize-pm.ll
@@ -0,0 +1,51 @@
+; RUN: opt -module-summary %s -o %t1.bc
+
+; Test SLP and Loop Vectorization are enabled by default at O2 and O3.
+; RUN: llvm-lto2 run %t1.bc -o %t2.o -O0 -r %t1.bc,foo,plx -debug-pass-manager \
+; RUN:  -use-new-pm -save-temps 2>&1 | FileCheck %s --check-prefix=CHECK-O0-SLP
+; RUN: llvm-dis %t2.o.1.4.opt.bc -o - | FileCheck %s --check-prefix=CHECK-O0-LPV
+
+; RUN: llvm-lto2 run %t1.bc -o %t3.o -O1 -r %t1.bc,foo,plx -debug-pass-manager \
+; RUN:  -use-new-pm -save-temps 2>&1 | FileCheck %s --check-prefix=CHECK-O1-SLP
+; RUN: llvm-dis %t3.o.1.4.opt.bc -o - | FileCheck %s --check-prefix=CHECK-O1-LPV
+
+; RUN: llvm-lto2 run %t1.bc -o %t4.o -O2 -r %t1.bc,foo,plx -debug-pass-manager \
+; RUN:  -use-new-pm -save-temps 2>&1 | FileCheck %s --check-prefix=CHECK-O2-SLP
+; RUN: llvm-dis %t4.o.1.4.opt.bc -o - | FileCheck %s --check-prefix=CHECK-O2-LPV
+
+; RUN: llvm-lto2 run %t1.bc -o %t5.o -O3 -r %t1.bc,foo,plx -debug-pass-manager \
+; RUN:  -use-new-pm -save-temps 2>&1 | FileCheck %s --check-prefix=CHECK-O3-SLP
+; RUN: llvm-dis %t5.o.1.4.opt.bc -o - | FileCheck %s --check-prefix=CHECK-O3-LPV
+
+; CHECK-O0-SLP-NOT: Running pass: SLPVectorizerPass
+; CHECK-O1-SLP-NOT: Running pass: SLPVectorizerPass
+; CHECK-O2-SLP: Running pass: SLPVectorizerPass
+; CHECK-O3-SLP: Running pass: SLPVectorizerPass
+; CHECK-O0-LPV-NOT: = !{!"llvm.loop.isvectorized", i32 1}
+; CHECK-O1-LPV-NOT: = !{!"llvm.loop.isvectorized", i32 1}
+; CHECK-O2-LPV: = !{!"llvm.loop.isvectorized", i32 1}
+; CHECK-O3-LPV: = !{!"llvm.loop.isvectorized", i32 1}
+
+target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+define i32 @foo(i32* %a) {
+entry:
+  br label %for.body
+
+for.body:
+  %indvars.iv = phi i64 [ 0, %entry ], [ %indvars.iv.next, %for.body ]
+  %red.05 = phi i32 [ 0, %entry ], [ %add, %for.body ]
+  %arrayidx = getelementptr inbounds i32, i32* %a, i64 %indvars.iv
+  %0 = load i32, i32* %arrayidx, align 4
+  %add = add nsw i32 %0, %red.05
+  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
+  %exitcond = icmp eq i64 %indvars.iv.next, 255
+  br i1 %exitcond, label %for.end, label %for.body, !llvm.loop !0
+
+for.end:
+  ret i32 %add
+}
+
+!0 = distinct !{!0, !1}
+!1 = !{!"llvm.loop.unroll.disable", i1 true}
diff --git a/llvm/tools/gold/gold-plugin.cpp b/llvm/tools/gold/gold-plugin.cpp
--- a/llvm/tools/gold/gold-plugin.cpp
+++ b/llvm/tools/gold/gold-plugin.cpp
@@ -860,6 +860,9 @@
   Conf.CGOptLevel = getCGOptLevel();
   Conf.DisableVerify = options::DisableVerify;
   Conf.OptLevel = options::OptLevel;
+  Conf.PTO.LoopVectorization = options::OptLevel > 1;
+  Conf.PTO.SLPVectorization = options::OptLevel > 1;
+
   if (options::Parallelism)
     Backend = createInProcessThinBackend(options::Parallelism);
   if (options::thinlto_index_only) {
diff --git a/llvm/tools/llvm-lto2/CMakeLists.txt b/llvm/tools/llvm-lto2/CMakeLists.txt
--- a/llvm/tools/llvm-lto2/CMakeLists.txt
+++ b/llvm/tools/llvm-lto2/CMakeLists.txt
@@ -9,6 +9,7 @@
   LTO
   MC
   Object
+  Passes
   Support
   Target
   )
diff --git a/llvm/tools/llvm-lto2/llvm-lto2.cpp b/llvm/tools/llvm-lto2/llvm-lto2.cpp
--- a/llvm/tools/llvm-lto2/llvm-lto2.cpp
+++ b/llvm/tools/llvm-lto2/llvm-lto2.cpp
@@ -270,6 +270,8 @@
   Conf.OverrideTriple = OverrideTriple;
   Conf.DefaultTriple = DefaultTriple;
   Conf.StatsFile = StatsFile;
+  Conf.PTO.LoopVectorization = Conf.OptLevel > 1;
+  Conf.PTO.SLPVectorization = Conf.OptLevel > 1;
 
   ThinBackend Backend;
   if (ThinLTODistributedIndexes)