diff --git a/clang/include/clang/Basic/DiagnosticDriverKinds.td b/clang/include/clang/Basic/DiagnosticDriverKinds.td
--- a/clang/include/clang/Basic/DiagnosticDriverKinds.td
+++ b/clang/include/clang/Basic/DiagnosticDriverKinds.td
@@ -250,6 +250,9 @@
 def err_drv_bitcode_unsupported_on_toolchain : Error<
   "-fembed-bitcode is not supported on versions of iOS prior to 6.0">;
 
+def err_drv_invalid_malign_branch_EQ : Error<
+  "invalid argument '%0' to -malign-branch=; each element must be one of: %1">;
+
 def warn_O4_is_O3 : Warning<"-O4 is equivalent to -O3">, InGroup<Deprecated>;
 def warn_drv_optimization_value : Warning<"optimization level '%0' is not supported; using '%1%2' instead">,
   InGroup<InvalidCommandLineArgument>;
diff --git a/clang/include/clang/Driver/Options.td b/clang/include/clang/Driver/Options.td
--- a/clang/include/clang/Driver/Options.td
+++ b/clang/include/clang/Driver/Options.td
@@ -2146,6 +2146,10 @@
 def malign_functions_EQ : Joined<["-"], "malign-functions=">, Group<clang_ignored_m_Group>;
 def malign_loops_EQ : Joined<["-"], "malign-loops=">, Group<clang_ignored_m_Group>;
 def malign_jumps_EQ : Joined<["-"], "malign-jumps=">, Group<clang_ignored_m_Group>;
+def malign_branch_EQ : CommaJoined<["-"], "malign-branch=">, Group<m_Group>;
+def malign_branch_boundary_EQ : Joined<["-"], "malign-branch-boundary=">, Group<m_Group>;
+def malign_branch_prefix_size_EQ : Joined<["-"], "malign-branch-prefix-size=">, Group<m_Group>;
+def mbranches_within_32B_boundaries : Flag<["-"], "mbranches-within-32B-boundaries">, Flags<[DriverOption]>, Group<m_Group>;
 def mfancy_math_387 : Flag<["-"], "mfancy-math-387">, Group<clang_ignored_m_Group>;
 def mlong_calls : Flag<["-"], "mlong-calls">, Group<m_Group>,
   HelpText<"Generate branches with extended addressability, usually via indirect jumps.">;
diff --git a/clang/lib/Driver/ToolChains/Clang.cpp b/clang/lib/Driver/ToolChains/Clang.cpp
--- a/clang/lib/Driver/ToolChains/Clang.cpp
+++ b/clang/lib/Driver/ToolChains/Clang.cpp
@@ -2012,8 +2012,60 @@
     CmdArgs.push_back("-mpacked-stack");
 }
 
+static void addX86AlignBranchArgs(const Driver &D, const ArgList &Args,
+  ArgStringList &CmdArgs) {
+  unsigned AlignBranchBoundary = 0, AlignBranchPrefixSize = 0;
+  std::string AlignBranch;
+  if (Args.hasArg(options::OPT_mbranches_within_32B_boundaries)) {
+    AlignBranchBoundary = 32;
+    AlignBranch = "fused,jcc,jmp";
+    AlignBranchPrefixSize = 5;
+  }
+  if (const Arg *A = Args.getLastArg(options::OPT_malign_branch_boundary_EQ)) {
+    StringRef Value = A->getValue();
+    if (Value.getAsInteger(10, AlignBranchBoundary) ||
+        AlignBranchBoundary < 16 || !llvm::isPowerOf2_64(AlignBranchBoundary))
+      D.Diag(diag::err_drv_invalid_argument_to_option)
+          << Value << A->getOption().getName();
+  }
+  if (const Arg *A = Args.getLastArg(options::OPT_malign_branch_EQ)) {
+    AlignBranch.clear();
+    for (StringRef T : A->getValues()) {
+      if (T != "fused" && T != "jcc" && T != "jmp" && T != "call" &&
+          T != "ret" && T != "indirect")
+        D.Diag(diag::err_drv_invalid_malign_branch_EQ)
+            << T << "fused, jcc, jmp, call, ret, indirect";
+      if (!AlignBranch.empty())
+        AlignBranch += ',';
+      AlignBranch += T;
+    }
+  }
+  if (const Arg *A =
+          Args.getLastArg(options::OPT_malign_branch_prefix_size_EQ)) {
+    StringRef Value = A->getValue();
+    if (Value.getAsInteger(10, AlignBranchPrefixSize) ||
+        AlignBranchPrefixSize > 5)
+      D.Diag(diag::err_drv_invalid_argument_to_option)
+          << Value << A->getOption().getName();
+  }
+  if (AlignBranchBoundary) {
+    CmdArgs.push_back("-mllvm");
+    CmdArgs.push_back(Args.MakeArgString("-x86-align-branch-boundary=" +
+                                         Twine(AlignBranchBoundary)));
+    CmdArgs.push_back("-mllvm");
+    std::replace(AlignBranch.begin(), AlignBranch.end(), ',', '+');
+    CmdArgs.push_back(Args.MakeArgString("-x86-align-branch=" + AlignBranch));
+    CmdArgs.push_back("-mllvm");
+    CmdArgs.push_back(Args.MakeArgString("-x86-align-branch-prefix-size=" +
+                                         Twine(AlignBranchPrefixSize)));
+  }
+}
+
 void Clang::AddX86TargetArgs(const ArgList &Args,
                              ArgStringList &CmdArgs) const {
+  const Driver &D = getToolChain().getDriver();
+  addX86AlignBranchArgs(D, Args, CmdArgs);
+
   if (!Args.hasFlag(options::OPT_mred_zone, options::OPT_mno_red_zone, true) ||
       Args.hasArg(options::OPT_mkernel) ||
       Args.hasArg(options::OPT_fapple_kext))
@@ -2043,10 +2095,10 @@
       CmdArgs.push_back("-mllvm");
       CmdArgs.push_back(Args.MakeArgString("-x86-asm-syntax=" + Value));
     } else {
-      getToolChain().getDriver().Diag(diag::err_drv_unsupported_option_argument)
+      D.Diag(diag::err_drv_unsupported_option_argument)
           << A->getOption().getName() << Value;
     }
-  } else if (getToolChain().getDriver().IsCLMode()) {
+  } else if (D.IsCLMode()) {
     CmdArgs.push_back("-mllvm");
     CmdArgs.push_back("-x86-asm-syntax=intel");
   }
@@ -6460,6 +6512,8 @@
 
 void ClangAs::AddX86TargetArgs(const ArgList &Args,
                                ArgStringList &CmdArgs) const {
+  addX86AlignBranchArgs(getToolChain().getDriver(), Args, CmdArgs);
+
   if (Arg *A = Args.getLastArg(options::OPT_masm_EQ)) {
     StringRef Value = A->getValue();
     if (Value == "intel" || Value == "att") {
diff --git a/clang/test/Driver/x86-malign-branch.c b/clang/test/Driver/x86-malign-branch.c
new file mode 100644
--- /dev/null
+++ b/clang/test/Driver/x86-malign-branch.c
@@ -0,0 +1,42 @@
+/// Test that -malign-branch* options are parsed and converted to -mllvm options.
+
+/// Test -malign-branch-boundary=
+// RUN: %clang -target x86_64 -malign-branch-boundary=16 %s -c -### 2>&1 | FileCheck %s --check-prefix=BOUNDARY
+// BOUNDARY: "-mllvm" "-x86-align-branch-boundary=16"
+
+// RUN: %clang -target x86_64 -malign-branch-boundary=8 %s -c -### 2>&1 | FileCheck %s --check-prefix=BOUNDARY-ERR
+// RUN: %clang -target x86_64 -malign-branch-boundary=15 %s -c -### 2>&1 | FileCheck %s --check-prefix=BOUNDARY-ERR
+// BOUNDARY-ERR: invalid argument {{.*}} to -malign-branch-boundary=
+
+/// Test -malign-branch=
+// RUN: %clang -target x86_64 -malign-branch-boundary=16 -malign-branch=fused,jcc,jmp %s -c -### %s 2>&1 | FileCheck %s --check-prefix=TYPE0
+// TYPE0: "-mllvm" "-x86-align-branch=fused+jcc+jmp"
+// RUN: %clang -target x86_64 -malign-branch-boundary=16 -malign-branch=fused,jcc,jmp,ret,call,indirect %s -c -### %s 2>&1 | FileCheck %s --check-prefix=TYPE1
+// TYPE1: "-mllvm" "-x86-align-branch=fused+jcc+jmp+ret+call+indirect"
+
+// RUN: %clang -target x86_64 -malign-branch=fused,foo,bar %s -c -### %s 2>&1 | FileCheck %s --check-prefix=TYPE-ERR
+// TYPE-ERR: invalid argument 'foo' to -malign-branch=; each element must be one of: fused, jcc, jmp, call, ret, indirect
+// TYPE-ERR: invalid argument 'bar' to -malign-branch=; each element must be one of: fused, jcc, jmp, call, ret, indirect
+
+/// Test -malign-branch-prefix-size=
+// RUN: %clang -target x86_64 -malign-branch-boundary=16 -malign-branch-prefix-size=0 %s -c -### 2>&1 | FileCheck %s --check-prefix=PREFIX-0
+// PREFIX-0: "-mllvm" "-x86-align-branch-prefix-size=0"
+// RUN: %clang -target x86_64 -malign-branch-boundary=16 -malign-branch-prefix-size=5 %s -c -### 2>&1 | FileCheck %s --check-prefix=PREFIX-5
+// PREFIX-5: "-mllvm" "-x86-align-branch-prefix-size=5"
+
+// RUN: %clang -target x86_64 -malign-branch-prefix-size=6 %s -c -### 2>&1 | FileCheck %s --check-prefix=PREFIX-6
+// PREFIX-6: invalid argument
+
+/// Test -mbranches-within-32B-boundaries
+// RUN: %clang -target x86_64 -mbranches-within-32B-boundaries %s -c -### 2>&1 | FileCheck %s --check-prefix=32B
+// 32B: "-mllvm" "-x86-align-branch-boundary=32" "-mllvm" "-x86-align-branch=fused+jcc+jmp" "-mllvm" "-x86-align-branch-prefix-size=5"
+/// Test that -malign-branch* can override individual values of -mbranches-within-32B-boundaries
+// RUN: %clang -target x86_64 -malign-branch=jcc -mbranches-within-32B-boundaries %s -c -### 2>&1 | FileCheck %s --check-prefix=32B-TYPE
+// 32B-TYPE:  "-mllvm" "-x86-align-branch-boundary=32" "-mllvm" "-x86-align-branch=jcc" "-mllvm" "-x86-align-branch-prefix-size=5"
+
+/// Unsupported on other targets.
+// RUN: %clang -target aarch64 -malign-branch=jmp %s -c -### 2>&1 | FileCheck --check-prefix=UNUSED %s
+// RUN: %clang -target aarch64 -malign-branch-boundary=7 %s -c -### 2>&1 | FileCheck --check-prefix=UNUSED %s
+// RUN: %clang -target aarch64 -malign-branch-prefix-size=15 %s -c -### 2>&1 | FileCheck --check-prefix=UNUSED %s
+// RUN: %clang -target aarch64 -mbranches-within-32B-boundaries %s -c -### 2>&1 | FileCheck --check-prefix=UNUSED %s
+// UNUSED: warning: argument unused
diff --git a/clang/test/Driver/x86-malign-branch.s b/clang/test/Driver/x86-malign-branch.s
new file mode 100644
--- /dev/null
+++ b/clang/test/Driver/x86-malign-branch.s
@@ -0,0 +1,13 @@
+/// Test that -malign-branch* are handled for assembly files.
+
+// RUN: %clang -target x86_64 -malign-branch-boundary=16 %s -c -### 2>&1 | FileCheck %s --check-prefix=BOUNDARY
+// BOUNDARY: "-mllvm" "-x86-align-branch-boundary=16"
+
+// RUN: %clang -target x86_64 -malign-branch-boundary=16 -malign-branch=fused,jcc,jmp %s -c -### %s 2>&1 | FileCheck %s --check-prefix=TYPE
+// TYPE: "-mllvm" "-x86-align-branch=fused+jcc+jmp"
+
+// RUN: %clang -target x86_64 -malign-branch-boundary=16 -malign-branch-prefix-size=5 %s -c -### 2>&1 | FileCheck %s --check-prefix=PREFIX
+// PREFIX: "-mllvm" "-x86-align-branch-prefix-size=5"
+
+// RUN: %clang -target x86_64 -mbranches-within-32B-boundaries %s -c -### 2>&1 | FileCheck %s --check-prefix=32B
+// 32B: "-mllvm" "-x86-align-branch-boundary=32" "-mllvm" "-x86-align-branch=fused+jcc+jmp" "-mllvm" "-x86-align-branch-prefix-size=5"