diff --git a/eng/common/templates/jobs/source-build.yml b/eng/common/templates/jobs/source-build.yml
index 00aa98eb3bfd3..b7737ffec3ef4 100644
--- a/eng/common/templates/jobs/source-build.yml
+++ b/eng/common/templates/jobs/source-build.yml
@@ -14,7 +14,7 @@ parameters:
   # This is the default platform provided by Arcade, intended for use by a managed-only repo.
   defaultManagedPlatform:
     name: 'Managed'
-    container: 'mcr.microsoft.com/dotnet-buildtools/prereqs:centos-7-3e800f1-20190501005343'
+    container: 'mcr.microsoft.com/dotnet-buildtools/prereqs:centos-7-20210714125435-9b5bbc2'
 
   # Defines the platforms on which to run build jobs. One job is created for each platform, and the
   # object in this array is sent to the job template as 'platform'. If no platforms are specified,
diff --git a/eng/native/configuretools.cmake b/eng/native/configuretools.cmake
index 37f3b4932cd22..136cd67925d0c 100644
--- a/eng/native/configuretools.cmake
+++ b/eng/native/configuretools.cmake
@@ -65,12 +65,14 @@ endif()
 
 if (NOT CLR_CMAKE_HOST_WIN32)
   # detect linker
-  set(ldVersion ${CMAKE_C_COMPILER};-Wl,--version)
+  separate_arguments(ldVersion UNIX_COMMAND "${CMAKE_C_COMPILER} ${CMAKE_SHARED_LINKER_FLAGS} -Wl,--version")
   execute_process(COMMAND ${ldVersion}
     ERROR_QUIET
     OUTPUT_VARIABLE ldVersionOutput)
 
-  if("${ldVersionOutput}" MATCHES "GNU ld" OR "${ldVersionOutput}" MATCHES "GNU gold" OR "${ldVersionOutput}" MATCHES "GNU linkers")
+  if("${ldVersionOutput}" MATCHES "LLD")
+    set(LD_LLVM 1)
+  elseif("${ldVersionOutput}" MATCHES "GNU ld" OR "${ldVersionOutput}" MATCHES "GNU gold" OR "${ldVersionOutput}" MATCHES "GNU linkers")
     set(LD_GNU 1)
   elseif("${ldVersionOutput}" MATCHES "Solaris Link")
     set(LD_SOLARIS 1)
diff --git a/eng/native/functions.cmake b/eng/native/functions.cmake
index 1ca230c3e534d..0d03cc3d2d46e 100644
--- a/eng/native/functions.cmake
+++ b/eng/native/functions.cmake
@@ -157,7 +157,7 @@ function(preprocess_files PreprocessedFilesList)
 endfunction()
 
 function(set_exports_linker_option exports_filename)
-    if(LD_GNU OR LD_SOLARIS)
+    if(LD_GNU OR LD_SOLARIS OR LD_LLVM)
         # Add linker exports file option
         if(LD_SOLARIS)
             set(EXPORTS_LINKER_OPTION -Wl,-M,${exports_filename} PARENT_SCOPE)
diff --git a/eng/native/init-compiler.sh b/eng/native/init-compiler.sh
index ca408e4d08816..567d18da4747a 100755
--- a/eng/native/init-compiler.sh
+++ b/eng/native/init-compiler.sh
@@ -22,6 +22,7 @@ minorVersion="$4"
 # clear the existing CC and CXX from environment
 CC=
 CXX=
+LDFLAGS=
 
 if [[ "$compiler" == "gcc" ]]; then cxxCompiler="g++"; fi
 
@@ -106,6 +107,15 @@ if [[ -z "$CC" ]]; then
     exit 1
 fi
 
+if [[ "$compiler" == "clang" ]]; then
+    if command -v "lld$desired_version" > /dev/null; then
+        # Only lld version >= 9 can be considered stable
+        if [[ "$majorVersion" -ge 9 ]]; then
+            LDFLAGS="-fuse-ld=lld"
+        fi
+    fi
+fi
+
 SCAN_BUILD_COMMAND="$(command -v "scan-build$desired_version")"
 
-export CC CXX SCAN_BUILD_COMMAND
+export CC CXX LDFLAGS SCAN_BUILD_COMMAND
diff --git a/eng/pipelines/common/platform-matrix.yml b/eng/pipelines/common/platform-matrix.yml
index defd34be84ae2..15fe948e92967 100644
--- a/eng/pipelines/common/platform-matrix.yml
+++ b/eng/pipelines/common/platform-matrix.yml
@@ -38,7 +38,7 @@ jobs:
       targetRid: linux-arm
       platform: Linux_arm
       container:
-        image: ubuntu-16.04-cross-20200413125008-09ec757
+        image: ubuntu-16.04-cross-20210719121212-8a8d3be
         registry: mcr
       jobParameters:
         runtimeFlavor: ${{ parameters.runtimeFlavor }}
@@ -64,7 +64,7 @@ jobs:
       targetRid: linux-arm64
       platform: Linux_arm64
       container:
-        image: ubuntu-16.04-cross-arm64-20201022204150-b2c2436
+        image: ubuntu-16.04-cross-arm64-20210719121212-8a8d3be
         registry: mcr
       jobParameters:
         runtimeFlavor: ${{ parameters.runtimeFlavor }}
@@ -91,7 +91,7 @@ jobs:
       targetRid: linux-musl-x64
       platform: Linux_musl_x64
       container:
-        image: alpine-3.9-WithNode-20200602002639-0fc54a3
+        image: alpine-3.9-WithNode-20210714125437-9b5bbc2
         registry: mcr
       jobParameters:
         runtimeFlavor: ${{ parameters.runtimeFlavor }}
@@ -116,7 +116,7 @@ jobs:
       targetRid: linux-musl-arm
       platform: Linux_musl_arm
       container:
-        image: ubuntu-16.04-cross-arm-alpine-20210409142327-044d5b9
+        image: ubuntu-16.04-cross-arm-alpine-20210719121212-044d5b9
         registry: mcr
       jobParameters:
         runtimeFlavor: ${{ parameters.runtimeFlavor }}
@@ -143,7 +143,7 @@ jobs:
       targetRid: linux-musl-arm64
       platform: Linux_musl_arm64
       container:
-        image: ubuntu-16.04-cross-arm64-alpine-20200413125008-406629a
+        image: ubuntu-16.04-cross-arm64-alpine-20210719121212-b2c2436
         registry: mcr
       jobParameters:
         runtimeFlavor: ${{ parameters.runtimeFlavor }}
@@ -169,7 +169,7 @@ jobs:
       targetRid: linux-x64
       platform: Linux_x64
       container:
-        image: centos-7-20201227183837-5fe0e50
+        image: centos-7-20210714125435-9b5bbc2
         registry: mcr
       jobParameters:
         runtimeFlavor: ${{ parameters.runtimeFlavor }}
@@ -193,7 +193,7 @@ jobs:
       targetRid: linux-x64
       platform: Linux_x64
       container:
-        image: centos-7-source-build-20210408124356-5d87b80
+        image: centos-7-source-build-20210714125450-5d87b80
         registry: mcr
       jobParameters:
         runtimeFlavor: ${{ parameters.runtimeFlavor }}
diff --git a/src/coreclr/pgosupport.cmake b/src/coreclr/pgosupport.cmake
index 6f07f1cd5ea8d..7c20ca3090ae3 100644
--- a/src/coreclr/pgosupport.cmake
+++ b/src/coreclr/pgosupport.cmake
@@ -30,7 +30,10 @@ function(add_pgo TargetName)
         else(CLR_CMAKE_HOST_WIN32)
             if(UPPERCASE_CMAKE_BUILD_TYPE STREQUAL RELEASE OR UPPERCASE_CMAKE_BUILD_TYPE STREQUAL RELWITHDEBINFO)
                 target_compile_options(${TargetName} PRIVATE -flto -fprofile-instr-generate)
-                set_property(TARGET ${TargetName} APPEND_STRING PROPERTY LINK_FLAGS " -flto -fuse-ld=gold -fprofile-instr-generate")
+                set_property(TARGET ${TargetName} APPEND_STRING PROPERTY LINK_FLAGS " -flto -fprofile-instr-generate")
+                if(NOT LD_LLVM)
+                    set_property(TARGET ${TargetName} APPEND_STRING PROPERTY LINK_FLAGS " -fuse-ld=gold")
+                endif()
             endif(UPPERCASE_CMAKE_BUILD_TYPE STREQUAL RELEASE OR UPPERCASE_CMAKE_BUILD_TYPE STREQUAL RELWITHDEBINFO)
         endif(CLR_CMAKE_HOST_WIN32)
     elseif(CLR_CMAKE_PGO_OPTIMIZE)
@@ -61,7 +64,10 @@ function(add_pgo TargetName)
                     if((CMAKE_CXX_COMPILER_ID MATCHES "Clang") AND (NOT CMAKE_CXX_COMPILER_VERSION VERSION_LESS 3.6))
                         if(HAVE_LTO)
                             target_compile_options(${TargetName} PRIVATE -flto -fprofile-instr-use=${ProfilePath} -Wno-profile-instr-out-of-date -Wno-profile-instr-unprofiled)
-                            set_property(TARGET ${TargetName} APPEND_STRING PROPERTY LINK_FLAGS " -flto -fuse-ld=gold -fprofile-instr-use=${ProfilePath}")
+                            set_property(TARGET ${TargetName} APPEND_STRING PROPERTY LINK_FLAGS " -flto -fprofile-instr-use=${ProfilePath}")
+                            if(NOT LD_LLVM)
+                                set_property(TARGET ${TargetName} APPEND_STRING PROPERTY LINK_FLAGS " -fuse-ld=gold")
+                            endif()
                         else(HAVE_LTO)
                             message(WARNING "LTO is not supported, skipping profile guided optimizations")
                         endif(HAVE_LTO)
diff --git a/src/coreclr/vm/CMakeLists.txt b/src/coreclr/vm/CMakeLists.txt
index f31e5a3ca12a6..d0f96523613bc 100644
--- a/src/coreclr/vm/CMakeLists.txt
+++ b/src/coreclr/vm/CMakeLists.txt
@@ -855,7 +855,6 @@ elseif(CLR_CMAKE_TARGET_ARCH_ARM64)
     set(VM_SOURCES_DAC_AND_WKS_ARCH
         ${ARCH_SOURCES_DIR}/stubs.cpp
         exceptionhandling.cpp
-        gcinfodecoder.cpp
     )
 
     set(VM_HEADERS_DAC_AND_WKS_ARCH
@@ -865,6 +864,7 @@ elseif(CLR_CMAKE_TARGET_ARCH_ARM64)
 
     set(VM_SOURCES_WKS_ARCH
         ${ARCH_SOURCES_DIR}/profiler.cpp
+        gcinfodecoder.cpp
     )
 
     if(CLR_CMAKE_HOST_UNIX)
diff --git a/src/coreclr/vm/arm/asmhelpers.S b/src/coreclr/vm/arm/asmhelpers.S
index 3faa8fe36846e..2780f95912f17 100644
--- a/src/coreclr/vm/arm/asmhelpers.S
+++ b/src/coreclr/vm/arm/asmhelpers.S
@@ -928,8 +928,9 @@ LOCAL_LABEL(CallCppHelper3):
     .endm
 
     .macro JIT_WRITEBARRIER_DESCRIPTOR name
-        .word \name
-        .word \name\()_End
+1:
+        .word \name-1b
+        .word \name\()_End-1b
         .word __\name\()__g_lowest_address_offset
         .word __\name\()__g_highest_address_offset
         .word __\name\()__g_ephemeral_low_offset
@@ -983,7 +984,9 @@ g_rgWriteBarrierDescriptors:
     LEAF_ENTRY JIT_WriteBarrier_Callable
 
     // Branch to the write barrier
-    ldr     r2, =JIT_WriteBarrier_Loc // or R3? See targetarm.h
+    ldr     r2, =JIT_WriteBarrier_Loc-(1f+4) // or R3? See targetarm.h
+1:
+    add     r2, pc
     ldr     pc, [r2]
 
     LEAF_END JIT_WriteBarrier_Callable
diff --git a/src/coreclr/vm/arm/pinvokestubs.S b/src/coreclr/vm/arm/pinvokestubs.S
index 8e7c468c36163..cd4928003b593 100644
--- a/src/coreclr/vm/arm/pinvokestubs.S
+++ b/src/coreclr/vm/arm/pinvokestubs.S
@@ -84,7 +84,9 @@
 
         PROLOG_PUSH  "{r4, lr}"
 
-        ldr     r1, =s_gsCookie
+        ldr     r1, =s_gsCookie-(1f+4)
+1:
+        add     r1, pc
         ldr     r1, [r1]
         str     r1, [r0]
         add     r4, r0, SIZEOF__GSCookie
@@ -92,7 +94,9 @@
         // r4 = pFrame
 
         // set first slot to the value of InlinedCallFrame::`vftable' (checked by runtime code)
-        ldr     r1, .L12
+        ldr     r1, =_ZTV16InlinedCallFrame+8-(2f+4)
+2:
+        add     r1, pc
         str     r1, [r4]
 
         mov     r1, 0
@@ -123,9 +127,6 @@
 
     NESTED_END JIT_PInvokeBegin, _TEXT
 
-.L12:
-    .word   _ZTV16InlinedCallFrame+8
-
 // ------------------------------------------------------------------
 // IN:
 // InlinedCallFrame (r0) = pointer to the InlinedCallFrame data, including the GS cookie slot (GS cookie right
@@ -145,7 +146,9 @@
         str     r2, [r1, #Thread_m_fPreemptiveGCDisabled]
 
         // Check return trap
-        ldr     r2, =g_TrapReturningThreads
+        ldr     r2, =g_TrapReturningThreads-(1f+4)
+1:
+        add     r2, pc
         ldr     r2, [r2]
         cbnz    r2, LOCAL_LABEL(RarePath)
 
diff --git a/src/coreclr/vm/arm/stubs.cpp b/src/coreclr/vm/arm/stubs.cpp
index 6e62df2370338..6b4f71f245530 100644
--- a/src/coreclr/vm/arm/stubs.cpp
+++ b/src/coreclr/vm/arm/stubs.cpp
@@ -281,8 +281,8 @@ void StubLinkerCPU::Init(void)
 // value of the global into a register.
 struct WriteBarrierDescriptor
 {
-    BYTE *  m_pFuncStart;                   // Pointer to the start of the barrier function
-    BYTE *  m_pFuncEnd;                     // Pointer to the end of the barrier function
+    DWORD   m_pFuncStart;                   // Offset to the start of the barrier function relative to this struct address
+    DWORD   m_pFuncEnd;                     // Offset to the end of the barrier function relative to this struct address
     DWORD   m_dw_g_lowest_address_offset;   // Offset of the instruction reading g_lowest_address
     DWORD   m_dw_g_highest_address_offset;  // Offset of the instruction reading g_highest_address
     DWORD   m_dw_g_ephemeral_low_offset;    // Offset of the instruction reading g_ephemeral_low
@@ -440,7 +440,7 @@ void UpdateGCWriteBarriers(bool postGrow = false)
     {
         // If the write barrier is being currently used (as in copied over to the patchable site)
         // then read the patch location from the table and use the offset to patch the target asm code
-        PBYTE to = FindWBMapping(pDesc->m_pFuncStart);
+        PBYTE to = FindWBMapping((BYTE *)pDesc + pDesc->m_pFuncStart);
         if(to)
         {
             to = (PBYTE)PCODEToPINSTR((PCODE)GetWriteBarrierCodeLocation(to));