Index: clang/include/clang/Driver/Options.td
===================================================================
--- clang/include/clang/Driver/Options.td
+++ clang/include/clang/Driver/Options.td
@@ -3418,7 +3418,7 @@
   HelpText<"Enable or disable Control Flow Guard checks and guard tables emission">,
   Values<"none,cf,cf-nochecks">;
 def mcpu_EQ : Joined<["-"], "mcpu=">, Group<m_Group>;
-def mmcu_EQ : Joined<["-"], "mmcu=">, Group<m_Group>;
+def mmcu_EQ : Joined<["-"], "mmcu=">, Group<m_Group>, Alias<mcpu_EQ>;
 def msim : Flag<["-"], "msim">, Group<m_Group>;
 def mdynamic_no_pic : Joined<["-"], "mdynamic-no-pic">, Group<m_Group>;
 def mfix_and_continue : Flag<["-"], "mfix-and-continue">, Group<clang_ignored_m_Group>;
Index: clang/lib/Driver/ToolChains/CommonArgs.cpp
===================================================================
--- clang/lib/Driver/ToolChains/CommonArgs.cpp
+++ clang/lib/Driver/ToolChains/CommonArgs.cpp
@@ -382,7 +382,7 @@
   }
 
   case llvm::Triple::avr:
-    if (const Arg *A = Args.getLastArg(options::OPT_mmcu_EQ))
+    if (const Arg *A = Args.getLastArg(options::OPT_mcpu_EQ))
       return A->getValue();
     return "";
 
Index: clang/lib/Driver/ToolChains/MSP430.cpp
===================================================================
--- clang/lib/Driver/ToolChains/MSP430.cpp
+++ clang/lib/Driver/ToolChains/MSP430.cpp
@@ -43,7 +43,7 @@
 static StringRef getHWMultLib(const ArgList &Args) {
   StringRef HWMult = Args.getLastArgValue(options::OPT_mhwmult_EQ, "auto");
   if (HWMult == "auto") {
-    HWMult = getSupportedHWMult(Args.getLastArg(options::OPT_mmcu_EQ));
+    HWMult = getSupportedHWMult(Args.getLastArg(options::OPT_mcpu_EQ));
   }
 
   return llvm::StringSwitch<StringRef>(HWMult)
@@ -55,7 +55,7 @@
 
 void msp430::getMSP430TargetFeatures(const Driver &D, const ArgList &Args,
                                      std::vector<StringRef> &Features) {
-  const Arg *MCU = Args.getLastArg(options::OPT_mmcu_EQ);
+  const Arg *MCU = Args.getLastArg(options::OPT_mcpu_EQ);
   if (MCU && !isSupportedMCU(MCU->getValue())) {
     D.Diag(diag::err_drv_clang_unsupported) << MCU->getValue();
     return;
@@ -161,7 +161,7 @@
                                             Action::OffloadKind) const {
   CC1Args.push_back("-nostdsysteminc");
 
-  const auto *MCUArg = DriverArgs.getLastArg(options::OPT_mmcu_EQ);
+  const auto *MCUArg = DriverArgs.getLastArg(options::OPT_mcpu_EQ);
   if (!MCUArg)
     return;
 
@@ -248,7 +248,7 @@
     return;
   }
 
-  const Arg *MCUArg = Args.getLastArg(options::OPT_mmcu_EQ);
+  const Arg *MCUArg = Args.getLastArg(options::OPT_mcpu_EQ);
   if (!MCUArg)
     return;
 
Index: clang/test/Driver/avr-mmcu.c
===================================================================
--- clang/test/Driver/avr-mmcu.c
+++ clang/test/Driver/avr-mmcu.c
@@ -1,81 +1,81 @@
-// A test for the propagation of the -mmcu option to -cc1 and -cc1as
+// A test for the propagation of the -mmcu/-mcpu option to -cc1 and -cc1as
 
 // RUN: %clang -### --target=avr -mmcu=attiny11 -save-temps %s 2>&1 | FileCheck -check-prefix=CHECK0 %s
+// RUN: %clang -### --target=avr -mcpu=attiny11 -save-temps %s 2>&1 | FileCheck -check-prefix=CHECK0 %s
 // CHECK0: "-cc1" {{.*}} "-target-cpu" "attiny11"
 // CHECK0: "-cc1as" {{.*}} "-target-cpu" "attiny11"
 
 // RUN: %clang -### --target=avr -mmcu=at90s2313 -save-temps %s 2>&1 | FileCheck -check-prefix=CHECK1 %s
+// RUN: %clang -### --target=avr -mcpu=at90s2313 -save-temps %s 2>&1 | FileCheck -check-prefix=CHECK1 %s
 // CHECK1: "-cc1" {{.*}} "-target-cpu" "at90s2313"
 // CHECK1: "-cc1as" {{.*}} "-target-cpu" "at90s2313"
 
 // RUN: %clang -### --target=avr -mmcu=at90s8515 -save-temps %s 2>&1 | FileCheck -check-prefix=CHECK2 %s
+// RUN: %clang -### --target=avr -mcpu=at90s8515 -save-temps %s 2>&1 | FileCheck -check-prefix=CHECK2 %s
 // CHECK2: "-cc1" {{.*}} "-target-cpu" "at90s8515"
 // CHECK2: "-cc1as" {{.*}} "-target-cpu" "at90s8515"
 
 // RUN: %clang -### --target=avr -mmcu=attiny13a -save-temps %s 2>&1 | FileCheck -check-prefix=CHECK3 %s
+// RUN: %clang -### --target=avr -mcpu=attiny13a -save-temps %s 2>&1 | FileCheck -check-prefix=CHECK3 %s
 // CHECK3: "-cc1" {{.*}} "-target-cpu" "attiny13a"
 // CHECK3: "-cc1as" {{.*}} "-target-cpu" "attiny13a"
 
 // RUN: %clang -### --target=avr -mmcu=attiny88 -save-temps %s 2>&1 | FileCheck -check-prefix=CHECK4 %s
+// RUN: %clang -### --target=avr -mcpu=attiny88 -save-temps %s 2>&1 | FileCheck -check-prefix=CHECK4 %s
 // CHECK4: "-cc1" {{.*}} "-target-cpu" "attiny88"
 // CHECK4: "-cc1as" {{.*}} "-target-cpu" "attiny88"
 
-// RUN: %clang -### --target=avr -mmcu=attiny88 -save-temps %s 2>&1 | FileCheck -check-prefix=CHECK5 %s
-// CHECK5: "-cc1" {{.*}} "-target-cpu" "attiny88"
-// CHECK5: "-cc1as" {{.*}} "-target-cpu" "attiny88"
-
 // RUN: %clang -### --target=avr -mmcu=atmega8u2 -save-temps %s 2>&1 | FileCheck -check-prefix=CHECK6 %s
+// RUN: %clang -### --target=avr -mcpu=atmega8u2 -save-temps %s 2>&1 | FileCheck -check-prefix=CHECK6 %s
 // CHECK6: "-cc1" {{.*}} "-target-cpu" "atmega8u2"
 // CHECK6: "-cc1as" {{.*}} "-target-cpu" "atmega8u2"
 
-// RUN: %clang -### --target=avr -mmcu=atmega8u2 -save-temps %s 2>&1 | FileCheck -check-prefix=CHECK7 %s
-// CHECK7: "-cc1" {{.*}} "-target-cpu" "atmega8u2"
-// CHECK7: "-cc1as" {{.*}} "-target-cpu" "atmega8u2"
-
 // RUN: %clang -### --target=avr -mmcu=atmega8a -save-temps %s 2>&1 | FileCheck -check-prefix=CHECK8 %s
+// RUN: %clang -### --target=avr -mcpu=atmega8a -save-temps %s 2>&1 | FileCheck -check-prefix=CHECK8 %s
 // CHECK8: "-cc1" {{.*}} "-target-cpu" "atmega8a"
 // CHECK8: "-cc1as" {{.*}} "-target-cpu" "atmega8a"
 
-// RUN: %clang -### --target=avr -mmcu=atmega8a -save-temps %s 2>&1 | FileCheck -check-prefix=CHECK9 %s
-// CHECK9: "-cc1" {{.*}} "-target-cpu" "atmega8a"
-// CHECK9: "-cc1as" {{.*}} "-target-cpu" "atmega8a"
-
 // RUN: %clang -### --target=avr -mmcu=atmega16a -save-temps %s 2>&1 | FileCheck -check-prefix=CHECKa %s
+// RUN: %clang -### --target=avr -mcpu=atmega16a -save-temps %s 2>&1 | FileCheck -check-prefix=CHECKa %s
 // CHECKa: "-cc1" {{.*}} "-target-cpu" "atmega16a"
 // CHECKa: "-cc1as" {{.*}} "-target-cpu" "atmega16a"
 
-// RUN: %clang -### --target=avr -mmcu=atmega16a -save-temps %s 2>&1 | FileCheck -check-prefix=CHECKb %s
-// CHECKb: "-cc1" {{.*}} "-target-cpu" "atmega16a"
-// CHECKb: "-cc1as" {{.*}} "-target-cpu" "atmega16a"
-
 // RUN: %clang -### --target=avr -mmcu=atmega128a -save-temps %s 2>&1 | FileCheck -check-prefix=CHECKc %s
+// RUN: %clang -### --target=avr -mcpu=atmega128a -save-temps %s 2>&1 | FileCheck -check-prefix=CHECKc %s
 // CHECKc: "-cc1" {{.*}} "-target-cpu" "atmega128a"
 // CHECKc: "-cc1as" {{.*}} "-target-cpu" "atmega128a"
 
 // RUN: %clang -### --target=avr -mmcu=atmega2560 -save-temps %s 2>&1 | FileCheck -check-prefix=CHECKd %s
+// RUN: %clang -### --target=avr -mcpu=atmega2560 -save-temps %s 2>&1 | FileCheck -check-prefix=CHECKd %s
 // CHECKd: "-cc1" {{.*}} "-target-cpu" "atmega2560"
 // CHECKd: "-cc1as" {{.*}} "-target-cpu" "atmega2560"
 
 // RUN: %clang -### --target=avr -mmcu=attiny10 -save-temps %s 2>&1 | FileCheck -check-prefix=CHECKe %s
+// RUN: %clang -### --target=avr -mcpu=attiny10 -save-temps %s 2>&1 | FileCheck -check-prefix=CHECKe %s
 // CHECKe: "-cc1" {{.*}} "-target-cpu" "attiny10"
 // CHECKe: "-cc1as" {{.*}} "-target-cpu" "attiny10"
 
 // RUN: %clang -### --target=avr -mmcu=atxmega16a4 -save-temps %s 2>&1 | FileCheck -check-prefix=CHECKf %s
+// RUN: %clang -### --target=avr -mcpu=atxmega16a4 -save-temps %s 2>&1 | FileCheck -check-prefix=CHECKf %s
 // CHECKf: "-cc1" {{.*}} "-target-cpu" "atxmega16a4"
 // CHECKf: "-cc1as" {{.*}} "-target-cpu" "atxmega16a4"
 
 // RUN: %clang -### --target=avr -mmcu=atxmega64b1 -save-temps %s 2>&1 | FileCheck -check-prefix=CHECKg %s
+// RUN: %clang -### --target=avr -mcpu=atxmega64b1 -save-temps %s 2>&1 | FileCheck -check-prefix=CHECKg %s
 // CHECKg: "-cc1" {{.*}} "-target-cpu" "atxmega64b1"
 // CHECKg: "-cc1as" {{.*}} "-target-cpu" "atxmega64b1"
 
 // RUN: %clang -### --target=avr -mmcu=atxmega64a1u -save-temps %s 2>&1 | FileCheck -check-prefix=CHECKh %s
+// RUN: %clang -### --target=avr -mcpu=atxmega64a1u -save-temps %s 2>&1 | FileCheck -check-prefix=CHECKh %s
 // CHECKh: "-cc1" {{.*}} "-target-cpu" "atxmega64a1u"
 // CHECKh: "-cc1as" {{.*}} "-target-cpu" "atxmega64a1u"
 
 // RUN: %clang -### --target=avr -mmcu=atxmega128a3u -save-temps %s 2>&1 | FileCheck -check-prefix=CHECKj %s
+// RUN: %clang -### --target=avr -mcpu=atxmega128a3u -save-temps %s 2>&1 | FileCheck -check-prefix=CHECKj %s
 // CHECKj: "-cc1" {{.*}} "-target-cpu" "atxmega128a3u"
 // CHECKj: "-cc1as" {{.*}} "-target-cpu" "atxmega128a3u"
 
 // RUN: %clang -### --target=avr -mmcu=atxmega128a4u -save-temps %s 2>&1 | FileCheck -check-prefix=CHECKi %s
+// RUN: %clang -### --target=avr -mcpu=atxmega128a4u -save-temps %s 2>&1 | FileCheck -check-prefix=CHECKi %s
 // CHECKi: "-cc1" {{.*}} "-target-cpu" "atxmega128a4u"
 // CHECKi: "-cc1as" {{.*}} "-target-cpu" "atxmega128a4u"
Index: clang/test/Driver/msp430-toolchain.c
===================================================================
--- clang/test/Driver/msp430-toolchain.c
+++ clang/test/Driver/msp430-toolchain.c
@@ -206,6 +206,9 @@
 // RUN: %clang -### %s --target=msp430 -mmcu=msp430g2553 \
 // RUN:   --sysroot=%S/Inputs/basic_msp430_tree 2>&1 \
 // RUN:   | FileCheck -check-prefix=LD-SCRIPT %s
+// RUN: %clang -### %s --target=msp430 -mcpu=msp430g2553 \
+// RUN:   --sysroot=%S/Inputs/basic_msp430_tree 2>&1 \
+// RUN:   | FileCheck -check-prefix=LD-SCRIPT %s
 // LD-SCRIPT: "{{.*}}/Inputs/basic_msp430_tree/lib/gcc/msp430-elf/8.3.1/../../..{{/|\\\\}}..{{/|\\\\}}bin{{/|\\\\}}msp430-elf-ld"
 // LD-SCRIPT: "-L{{.*}}/Inputs/basic_msp430_tree{{/|\\\\}}include"
 // LD-SCRIPT: "-Tmsp430g2553.ld"
@@ -214,6 +217,10 @@
 // RUN:   --sysroot=%S/Inputs/basic_msp430_tree \
 // RUN:   -T custom_script.ld 2>&1 \
 // RUN:   | FileCheck -check-prefix=CUSTOM-LD-SCRIPT %s
+// RUN: %clang -### %s --target=msp430 -mcpu=msp430g2553 \
+// RUN:   --sysroot=%S/Inputs/basic_msp430_tree \
+// RUN:   -T custom_script.ld 2>&1 \
+// RUN:   | FileCheck -check-prefix=CUSTOM-LD-SCRIPT %s
 // CUSTOM-LD-SCRIPT: "{{.*}}/Inputs/basic_msp430_tree/lib/gcc/msp430-elf/8.3.1/../../..{{/|\\\\}}..{{/|\\\\}}bin{{/|\\\\}}msp430-elf-ld"
 // CUSTOM-LD_SCRIPT-NOT: "-Tmsp430g2553.ld"
 // CUSTOM-LD-SCRIPT: "-T" "custom_script.ld"
@@ -223,6 +230,8 @@
 
 // RUN: %clang -### %s --target=msp430 -mmcu=msp430g2553 \
 // RUN:   -msim -rtlib=libgcc --sysroot=%S/Inputs/basic_msp430_tree > %t 2>&1
+// RUN: %clang -### %s --target=msp430 -mcpu=msp430g2553 \
+// RUN:   -msim -rtlib=libgcc --sysroot=%S/Inputs/basic_msp430_tree > %t 2>&1
 // RUN: FileCheck -check-prefix=SIMULATOR-POS %s < %t
 // RUN: FileCheck -check-prefix=SIMULATOR-NEG %s < %t
 // SIMULATOR-POS: "{{.*}}/Inputs/basic_msp430_tree/lib/gcc/msp430-elf/8.3.1/../../..{{/|\\\\}}..{{/|\\\\}}bin{{/|\\\\}}msp430-elf-ld"