Triple::normalize: Use none as OS for XX-none-ABI (#89638)

When parsing a 3-component triple, after we determine Arch and Env, if
the middle component is "none", treat it as OS instead of Vendor.

See:
https://discourse.llvm.org/t/rfc-baremetal-target-triple-normalization/78524
Fixes: #89582.

11 files changed, 58 insertions, 52 deletions

diff --git a/clang/docs/Multilib.rst b/clang/docs/Multilib.rst
index ab737e43b97d..063fe9a336f2 100644
--- a/clang/docs/Multilib.rst
+++ b/clang/docs/Multilib.rst
@@ -188,9 +188,9 @@ For a more comprehensive example see
   - Dir: thumb/v6-m
     # List of one or more normalized command line options, as generated by Clang
     # from the command line options or from Mappings below.
-    # Here, if the flags are a superset of {target=thumbv6m-none-unknown-eabi}
+    # Here, if the flags are a superset of {target=thumbv6m-unknown-none-eabi}
     # then this multilib variant will be considered a match.
-    Flags: [--target=thumbv6m-none-unknown-eabi]
+    Flags: [--target=thumbv6m-unknown-none-eabi]
 
   # Similarly, a multilib variant targeting Arm v7-M with an FPU (floating
   # point unit).
diff --git a/clang/test/Driver/arm-ias-Wa.s b/clang/test/Driver/arm-ias-Wa.s
index b82ce8dfb31a..5e9518ed2dc4 100644
--- a/clang/test/Driver/arm-ias-Wa.s
+++ b/clang/test/Driver/arm-ias-Wa.s
@@ -71,7 +71,7 @@
 
 // RUN: %clang -target armv7r-none-eabi -c %s -### 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHECK-R-PROFILE %s
-// CHECK-R-PROFILE: "-triple" "armv7r-none-unknown-eabi"
+// CHECK-R-PROFILE: "-triple" "armv7r-unknown-none-eabi"
 
 // RUN: %clang -target armv7m-none-eabi -c %s -### 2>&1 \
 // RUN: %clang -target thumbv7m-none-eabi -c %s -### 2>&1 \
diff --git a/clang/test/Driver/arm-triple.c b/clang/test/Driver/arm-triple.c
index fa9f7b189c82..1fb2b5afe22a 100644
--- a/clang/test/Driver/arm-triple.c
+++ b/clang/test/Driver/arm-triple.c
@@ -7,7 +7,7 @@
 // RUN: %clang -print-effective-triple \
 // RUN:   --target=arm-none-eabihf -march=armv4t -mfloat-abi=softfp \
 // RUN:   | FileCheck %s --check-prefix=CHECK-DEFAULT
-// CHECK-DEFAULT: armv4t-none-unknown-eabi
+// CHECK-DEFAULT: armv4t-unknown-none-eabi
 
 // RUN: %clang -print-effective-triple \
 // RUN:   --target=armeb-none-eabi \
@@ -15,7 +15,7 @@
 // RUN: %clang -print-effective-triple \
 // RUN:   --target=arm-none-eabi -mbig-endian \
 // RUN:   | FileCheck %s --check-prefix=CHECK-EB
-// CHECK-EB: armebv4t-none-unknown-eabi
+// CHECK-EB: armebv4t-unknown-none-eabi
 
 // RUN: %clang -print-effective-triple \
 // RUN:   --target=arm-none-eabihf -march=armv4t \
@@ -23,7 +23,7 @@
 // RUN: %clang -print-effective-triple \
 // RUN:   --target=arm-none-eabi -mfloat-abi=hard \
 // RUN:   | FileCheck %s --check-prefix=CHECK-HF
-// CHECK-HF: armv4t-none-unknown-eabihf
+// CHECK-HF: armv4t-unknown-none-eabihf
 
 // RUN: %clang -print-effective-triple \
 // RUN:   --target=armeb-none-eabihf -march=armv4t \
@@ -37,7 +37,7 @@
 // RUN: %clang -print-effective-triple \
 // RUN:   --target=arm-none-eabi -mbig-endian -mfloat-abi=hard \
 // RUN:   | FileCheck %s --check-prefix=CHECK-EB-HF
-// CHECK-EB-HF: armebv4t-none-unknown-eabihf
+// CHECK-EB-HF: armebv4t-unknown-none-eabihf
 
 // RUN: %clang -print-effective-triple \
 // RUN:   --target=arm-none-eabi -march=armv8m.main -mbig-endian -mfloat-abi=hard \
@@ -45,4 +45,4 @@
 // RUN: %clang -print-effective-triple \
 // RUN:   --target=arm-none-eabi -mcpu=cortex-m33 -mbig-endian -mfloat-abi=hard \
 // RUN:   | FileCheck %s --check-prefix=CHECK-V8M-EB-HF
-// CHECK-V8M-EB-HF: thumbebv8m.main-none-unknown-eabihf
+// CHECK-V8M-EB-HF: thumbebv8m.main-unknown-none-eabihf
diff --git a/clang/test/Driver/baremetal-multilib-layered.yaml b/clang/test/Driver/baremetal-multilib-layered.yaml
index 2f86f8e3ea4f..a525436d8122 100644
--- a/clang/test/Driver/baremetal-multilib-layered.yaml
+++ b/clang/test/Driver/baremetal-multilib-layered.yaml
@@ -18,7 +18,7 @@
 # RUN: %T/baremetal_multilib_layered/bin/clang -no-canonical-prefixes -x c++ %s -### -o %t.out 2>&1 \
 # RUN:     --target=thumbv7m-none-eabi -mfloat-abi=softfp --sysroot= \
 # RUN:   | FileCheck -DSYSROOT=%T/baremetal_multilib_layered %s
-# CHECK:      "-cc1" "-triple" "thumbv7m-none-unknown-eabi"
+# CHECK:      "-cc1" "-triple" "thumbv7m-unknown-none-eabi"
 # CHECK-SAME: "-internal-isystem" "[[SYSROOT]]/bin/../lib/clang-runtimes/softfp/include/c++/v1"
 # CHECK-SAME: "-internal-isystem" "[[SYSROOT]]/bin/../lib/clang-runtimes/soft/include/c++/v1"
 # CHECK-SAME: "-internal-isystem" "[[SYSROOT]]/bin/../lib/clang-runtimes/softfp/include"
diff --git a/clang/test/Driver/baremetal-multilib.yaml b/clang/test/Driver/baremetal-multilib.yaml
index 3f026cbeb437..9ed83e4aec83 100644
--- a/clang/test/Driver/baremetal-multilib.yaml
+++ b/clang/test/Driver/baremetal-multilib.yaml
@@ -11,7 +11,7 @@
 # RUN: %T/baremetal_multilib/bin/clang -no-canonical-prefixes -x c++ %s -### -o %t.out 2>&1 \
 # RUN:     --target=thumbv8m.main-none-eabihf --sysroot= \
 # RUN:   | FileCheck -DSYSROOT=%T/baremetal_multilib %s
-# CHECK:      "-cc1" "-triple" "thumbv8m.main-none-unknown-eabihf"
+# CHECK:      "-cc1" "-triple" "thumbv8m.main-unknown-none-eabihf"
 # CHECK-SAME: "-internal-isystem" "[[SYSROOT]]/bin/../lib/clang-runtimes/arm-none-eabi/thumb/v8-m.main/fp/include/c++/v1"
 # CHECK-SAME: "-internal-isystem" "[[SYSROOT]]/bin/../lib/clang-runtimes/arm-none-eabi/thumb/v8-m.main/fp/include"
 # CHECK-SAME: "-x" "c++" "{{.*}}baremetal-multilib.yaml"
@@ -24,11 +24,11 @@
 # RUN:     --target=thumbv7em-none-eabi -mfpu=fpv4-sp-d16 --sysroot= \
 # RUN:   | FileCheck --check-prefix=CHECK-NO-MATCH %s
 # CHECK-NO-MATCH: warning: no multilib found matching flags:
-# CHECK-NO-MATCH-SAME: --target=thumbv7em-none-unknown-eabi
+# CHECK-NO-MATCH-SAME: --target=thumbv7em-unknown-none-eabi
 # CHECK-NO-MATCH: note: available multilibs are:
-# CHECK-NO-MATCH: --target=thumbv6m-none-unknown-eabi -mfpu=none
-# CHECK-NO-MATCH: --target=thumbv7m-none-unknown-eabi -mfpu=none
-# CHECK-NO-MATCH: --target=thumbv7em-none-unknown-eabi -mfpu=none
+# CHECK-NO-MATCH: --target=thumbv6m-unknown-none-eabi -mfpu=none
+# CHECK-NO-MATCH: --target=thumbv7m-unknown-none-eabi -mfpu=none
+# CHECK-NO-MATCH: --target=thumbv7em-unknown-none-eabi -mfpu=none
 
 # RUN: %T/baremetal_multilib/bin/clang -no-canonical-prefixes -print-multi-directory 2>&1 \
 # RUN:     --target=thumbv8m.main-none-eabihf --sysroot= \
@@ -38,16 +38,16 @@
 # RUN: %T/baremetal_multilib/bin/clang -no-canonical-prefixes -print-multi-lib 2>&1 \
 # RUN:     --target=arm-none-eabi --sysroot= \
 # RUN:   | FileCheck --check-prefix=CHECK-PRINT-MULTI-LIB %s
-# CHECK-PRINT-MULTI-LIB: arm-none-eabi/thumb/v6-m/nofp;@-target=thumbv6m-none-unknown-eabi@mfpu=none
-# CHECK-PRINT-MULTI-LIB: arm-none-eabi/thumb/v7-m/nofp;@-target=thumbv7m-none-unknown-eabi@mfpu=none
-# CHECK-PRINT-MULTI-LIB: arm-none-eabi/thumb/v7e-m/nofp;@-target=thumbv7em-none-unknown-eabi@mfpu=none
-# CHECK-PRINT-MULTI-LIB: arm-none-eabi/thumb/v8-m.main/nofp;@-target=thumbv8m.main-none-unknown-eabi@mfpu=none
-# CHECK-PRINT-MULTI-LIB: arm-none-eabi/thumb/v8.1-m.main/nofp/nomve;@-target=thumbv8.1m.main-none-unknown-eabi@mfpu=none
-# CHECK-PRINT-MULTI-LIB: arm-none-eabi/thumb/v7e-m/fpv4_sp_d16;@-target=thumbv7em-none-unknown-eabihf@mfpu=fpv4-sp-d16
-# CHECK-PRINT-MULTI-LIB: arm-none-eabi/thumb/v7e-m/fpv5_d16;@-target=thumbv7em-none-unknown-eabihf@mfpu=fpv5-d16
-# CHECK-PRINT-MULTI-LIB: arm-none-eabi/thumb/v8-m.main/fp;@-target=thumbv8m.main-none-unknown-eabihf@mfpu=fpv5-d16
-# CHECK-PRINT-MULTI-LIB: arm-none-eabi/thumb/v8.1-m.main/fp;@-target=thumbv8.1m.main-none-unknown-eabihf@mfpu=fp-armv8-fullfp16-sp-d16
-# CHECK-PRINT-MULTI-LIB: arm-none-eabi/thumb/v8.1-m.main/nofp/mve;@-target=thumbv8.1m.main-none-unknown-eabihf@march=thumbv8.1m.main+mve@mfpu=none
+# CHECK-PRINT-MULTI-LIB: arm-none-eabi/thumb/v6-m/nofp;@-target=thumbv6m-unknown-none-eabi@mfpu=none
+# CHECK-PRINT-MULTI-LIB: arm-none-eabi/thumb/v7-m/nofp;@-target=thumbv7m-unknown-none-eabi@mfpu=none
+# CHECK-PRINT-MULTI-LIB: arm-none-eabi/thumb/v7e-m/nofp;@-target=thumbv7em-unknown-none-eabi@mfpu=none
+# CHECK-PRINT-MULTI-LIB: arm-none-eabi/thumb/v8-m.main/nofp;@-target=thumbv8m.main-unknown-none-eabi@mfpu=none
+# CHECK-PRINT-MULTI-LIB: arm-none-eabi/thumb/v8.1-m.main/nofp/nomve;@-target=thumbv8.1m.main-unknown-none-eabi@mfpu=none
+# CHECK-PRINT-MULTI-LIB: arm-none-eabi/thumb/v7e-m/fpv4_sp_d16;@-target=thumbv7em-unknown-none-eabihf@mfpu=fpv4-sp-d16
+# CHECK-PRINT-MULTI-LIB: arm-none-eabi/thumb/v7e-m/fpv5_d16;@-target=thumbv7em-unknown-none-eabihf@mfpu=fpv5-d16
+# CHECK-PRINT-MULTI-LIB: arm-none-eabi/thumb/v8-m.main/fp;@-target=thumbv8m.main-unknown-none-eabihf@mfpu=fpv5-d16
+# CHECK-PRINT-MULTI-LIB: arm-none-eabi/thumb/v8.1-m.main/fp;@-target=thumbv8.1m.main-unknown-none-eabihf@mfpu=fp-armv8-fullfp16-sp-d16
+# CHECK-PRINT-MULTI-LIB: arm-none-eabi/thumb/v8.1-m.main/nofp/mve;@-target=thumbv8.1m.main-unknown-none-eabihf@march=thumbv8.1m.main+mve@mfpu=none
 
 # RUN: %T/baremetal_multilib/bin/clang -no-canonical-prefixes -x assembler -mexecute-only \
 # RUN:     --target=arm-none-eabi --sysroot= %s -c -### 2>&1 \
@@ -86,37 +86,37 @@ MultilibVersion: 1.0
 
 Variants:
 - Dir: arm-none-eabi/arm/v4t
-  Flags: [--target=armv4t-none-unknown-eabi]
+  Flags: [--target=armv4t-unknown-none-eabi]
 
 - Dir: arm-none-eabi/thumb/v6-m/nofp
-  Flags: [--target=thumbv6m-none-unknown-eabi, -mfpu=none]
+  Flags: [--target=thumbv6m-unknown-none-eabi, -mfpu=none]
 
 - Dir: arm-none-eabi/thumb/v7-m/nofp
-  Flags: [--target=thumbv7m-none-unknown-eabi, -mfpu=none]
+  Flags: [--target=thumbv7m-unknown-none-eabi, -mfpu=none]
 
 - Dir: arm-none-eabi/thumb/v7e-m/nofp
-  Flags: [--target=thumbv7em-none-unknown-eabi, -mfpu=none]
+  Flags: [--target=thumbv7em-unknown-none-eabi, -mfpu=none]
 
 - Dir: arm-none-eabi/thumb/v8-m.main/nofp
-  Flags: [--target=thumbv8m.main-none-unknown-eabi, -mfpu=none]
+  Flags: [--target=thumbv8m.main-unknown-none-eabi, -mfpu=none]
 
 - Dir: arm-none-eabi/thumb/v8.1-m.main/nofp/nomve
-  Flags: [--target=thumbv8.1m.main-none-unknown-eabi, -mfpu=none]
+  Flags: [--target=thumbv8.1m.main-unknown-none-eabi, -mfpu=none]
 
 - Dir: arm-none-eabi/thumb/v7e-m/fpv4_sp_d16
-  Flags: [--target=thumbv7em-none-unknown-eabihf, -mfpu=fpv4-sp-d16]
+  Flags: [--target=thumbv7em-unknown-none-eabihf, -mfpu=fpv4-sp-d16]
 
 - Dir: arm-none-eabi/thumb/v7e-m/fpv5_d16
-  Flags: [--target=thumbv7em-none-unknown-eabihf, -mfpu=fpv5-d16]
+  Flags: [--target=thumbv7em-unknown-none-eabihf, -mfpu=fpv5-d16]
 
 - Dir: arm-none-eabi/thumb/v8-m.main/fp
-  Flags: [--target=thumbv8m.main-none-unknown-eabihf, -mfpu=fpv5-d16]
+  Flags: [--target=thumbv8m.main-unknown-none-eabihf, -mfpu=fpv5-d16]
 
 - Dir: arm-none-eabi/thumb/v8.1-m.main/fp
-  Flags: [--target=thumbv8.1m.main-none-unknown-eabihf, -mfpu=fp-armv8-fullfp16-sp-d16]
+  Flags: [--target=thumbv8.1m.main-unknown-none-eabihf, -mfpu=fp-armv8-fullfp16-sp-d16]
 
 - Dir: arm-none-eabi/thumb/v8.1-m.main/nofp/mve
-  Flags: [--target=thumbv8.1m.main-none-unknown-eabihf, -march=thumbv8.1m.main+mve, -mfpu=none]
+  Flags: [--target=thumbv8.1m.main-unknown-none-eabihf, -march=thumbv8.1m.main+mve, -mfpu=none]
 
 
 # The second section of the file is a map from auto-detected flags
@@ -126,17 +126,17 @@ Variants:
 # All flags in the "Flags" list will be added if an argument matches.
 Mappings:
 # For v8m.base (and potential later v8m baseline versions) use v6m
-- Match: --target=thumbv8(\.[0-9]+)?m\.base-none-unknown-eabi
-  Flags: [--target=thumbv6m-none-unknown-eabi]
+- Match: --target=thumbv8(\.[0-9]+)?m\.base-unknown-none-eabi
+  Flags: [--target=thumbv6m-unknown-none-eabi]
 # Match versions after v8.1m.main. We assume that v8.2m (if/when it exists) will
 # be backwards compatible with v8.1m.
 # The alternative is to not recognise later versions, and require that
 # this multilib spec is updated before it can be used with newer
 # architecture versions.
-- Match: --target=thumbv8\.[1-9]m\.main-none-unknown-eabi
-  Flags: [--target=thumbv8.1m.main-none-unknown-eabi]
-- Match: --target=thumbv8\.[1-9]m\.main-none-unknown-eabihf
-  Flags: [--target=thumbv8.1m.main-none-unknown-eabihf]
+- Match: --target=thumbv8\.[1-9]m\.main-unknown-none-eabi
+  Flags: [--target=thumbv8.1m.main-unknown-none-eabi]
+- Match: --target=thumbv8\.[1-9]m\.main-unknown-none-eabihf
+  Flags: [--target=thumbv8.1m.main-unknown-none-eabihf]
 
 - Match: -march=thumbv8\.[1-9]m\.main.*\+mve($|\+).*
   Flags: [-march=thumbv8.1m.main+mve]
diff --git a/clang/test/Driver/baremetal-sysroot.cpp b/clang/test/Driver/baremetal-sysroot.cpp
index bbc608809d0e..18654be33b87 100644
--- a/clang/test/Driver/baremetal-sysroot.cpp
+++ b/clang/test/Driver/baremetal-sysroot.cpp
@@ -12,7 +12,7 @@
 // RUN: %T/baremetal_default_sysroot/bin/clang -no-canonical-prefixes %s -### -o %t.o 2>&1 \
 // RUN:     -target armv6m-none-eabi --sysroot= \
 // RUN:   | FileCheck --check-prefix=CHECK-V6M-C %s
-// CHECK-V6M-C: "{{.*}}clang{{.*}}" "-cc1" "-triple" "thumbv6m-none-unknown-eabi"
+// CHECK-V6M-C: "{{.*}}clang{{.*}}" "-cc1" "-triple" "thumbv6m-unknown-none-eabi"
 // CHECK-V6M-C-SAME: "-internal-isystem" "{{.*}}/baremetal_default_sysroot{{[/\\]+}}bin{{[/\\]+}}..{{[/\\]+}}lib{{[/\\]+}}clang-runtimes{{[/\\]+}}armv6m-none-eabi{{[/\\]+}}include{{[/\\]+}}c++{{[/\\]+}}v1"
 // CHECk-V6M-C-SAME: "-internal-isystem" "{{.*}}/baremetal_default_sysroot{{[/\\]+}}bin{{[/\\]+}}..{{[/\\]+}}lib{{[/\\]+}}clang-runtimes{{[/\\]+}}armv6m-none-eabi{{[/\\]+}}include"
 // CHECK-V6M-C-SAME: "-x" "c++" "{{.*}}baremetal-sysroot.cpp"
diff --git a/clang/test/Driver/baremetal.cpp b/clang/test/Driver/baremetal.cpp
index 657611bb3f38..cc14f045df3f 100644
--- a/clang/test/Driver/baremetal.cpp
+++ b/clang/test/Driver/baremetal.cpp
@@ -9,7 +9,7 @@
 // RUN:     -L some/directory/user/asked/for \
 // RUN:     --sysroot=%S/Inputs/baremetal_arm \
 // RUN:   | FileCheck --check-prefix=CHECK-V6M-C %s
-// CHECK-V6M-C:      "-cc1" "-triple" "thumbv6m-none-unknown-eabi"
+// CHECK-V6M-C:      "-cc1" "-triple" "thumbv6m-unknown-none-eabi"
 // CHECK-V6M-C-SAME: "-resource-dir" "[[RESOURCE_DIR:[^"]+]]"
 // CHECK-V6M-C-SAME: "-isysroot" "[[SYSROOT:[^"]*]]"
 // CHECK-V6M-C-SAME: "-internal-isystem" "[[SYSROOT]]{{[/\\]+}}include{{[/\\]+}}c++{{[/\\]+}}v1"
diff --git a/clang/test/Driver/print-multi-selection-flags.c b/clang/test/Driver/print-multi-selection-flags.c
index 06a12db9d977..9f58d1b557fd 100644
--- a/clang/test/Driver/print-multi-selection-flags.c
+++ b/clang/test/Driver/print-multi-selection-flags.c
@@ -5,27 +5,27 @@
 // CHECK-FUCHSIA: --target=aarch64-unknown-fuchsia
 
 // RUN: %clang -print-multi-flags-experimental --target=arm-none-eabi -mfloat-abi=soft -fno-exceptions -fno-rtti | FileCheck --check-prefix=CHECK-ARMV4T %s
-// CHECK-ARMV4T: --target=armv4t-none-unknown-eabi
+// CHECK-ARMV4T: --target=armv4t-unknown-none-eabi
 // CHECK-ARMV4T: -mfloat-abi=soft
 // CHECK-ARMV4T: -mfpu=none
 
 // RUN: %clang -print-multi-flags-experimental --target=armv7em-none-eabi -mfloat-abi=softfp | FileCheck --check-prefix=CHECK-SOFTFP %s
-// CHECK-SOFTFP: --target=thumbv7em-none-unknown-eabi
+// CHECK-SOFTFP: --target=thumbv7em-unknown-none-eabi
 // CHECK-SOFTFP: -mfloat-abi=softfp
 // CHECK-SOFTFP: -mfpu=fpv4-sp-d16
 
 // RUN: %clang -print-multi-flags-experimental --target=arm-none-eabihf -march=armv7em -mfpu=fpv5-d16 | FileCheck --check-prefix=CHECK-HARD %s
-// CHECK-HARD: --target=thumbv7em-none-unknown-eabihf
+// CHECK-HARD: --target=thumbv7em-unknown-none-eabihf
 // CHECK-HARD: -mfloat-abi=hard
 // CHECK-HARD: -mfpu=fpv5-d16
 
 // RUN: %clang -print-multi-flags-experimental --target=arm-none-eabi -mfloat-abi=soft -march=armv8-m.main+nofp | FileCheck --check-prefix=CHECK-V8MMAIN-NOFP %s
-// CHECK-V8MMAIN-NOFP: --target=thumbv8m.main-none-unknown-eabi
+// CHECK-V8MMAIN-NOFP: --target=thumbv8m.main-unknown-none-eabi
 // CHECK-V8MMAIN-NOFP: -mfloat-abi=soft
 // CHECK-V8MMAIN-NOFP: -mfpu=none
 
 // RUN: %clang -print-multi-flags-experimental --target=arm-none-eabi -mfloat-abi=hard -march=armv8.1m.main+mve.fp | FileCheck --check-prefix=CHECK-MVE %s
-// CHECK-MVE: --target=thumbv8.1m.main-none-unknown-eabihf
+// CHECK-MVE: --target=thumbv8.1m.main-unknown-none-eabihf
 // CHECK-MVE: -march=thumbv8.1m.main{{.*}}+mve{{.*}}+mve.fp{{.*}}
 // CHECK-MVE: -mfloat-abi=hard
 // CHECK-MVE: -mfpu=fp-armv8-fullfp16-sp-d16
@@ -51,10 +51,10 @@
 // CHECK-M85_NO_FP_DP: -mfpu=fp-armv8-fullfp16-sp-d16
 
 // RUN: %clang -print-multi-flags-experimental --target=aarch64-none-elf -march=armv8-a+lse | FileCheck --check-prefix=CHECK-LSE %s
-// CHECK-LSE: --target=aarch64-none-unknown-elf
+// CHECK-LSE: --target=aarch64-unknown-none-elf
 // CHECK-LSE: -march=armv8-a{{.*}}+lse{{.*}}
 
 // RUN: %clang -print-multi-flags-experimental --target=aarch64-none-elf -march=armv8.5-a+sve+sve2 | FileCheck --check-prefix=CHECK-SVE2 %s
 // RUN: %clang -print-multi-flags-experimental --target=aarch64-none-elf -march=armv9-a            | FileCheck --check-prefix=CHECK-SVE2 %s
-// CHECK-SVE2: --target=aarch64-none-unknown-elf
+// CHECK-SVE2: --target=aarch64-unknown-none-elf
 // CHECK-SVE2: -march=armv{{.*}}-a{{.*}}+simd{{.*}}+sve{{.*}}+sve2{{.*}}
diff --git a/clang/unittests/Interpreter/IncrementalCompilerBuilderTest.cpp b/clang/unittests/Interpreter/IncrementalCompilerBuilderTest.cpp
index f729566f7efd..c4a40071f55c 100644
--- a/clang/unittests/Interpreter/IncrementalCompilerBuilderTest.cpp
+++ b/clang/unittests/Interpreter/IncrementalCompilerBuilderTest.cpp
@@ -40,7 +40,7 @@ TEST(IncrementalCompilerBuilder, SetTargetTriple) {
   auto CB = clang::IncrementalCompilerBuilder();
   CB.SetTargetTriple("armv6-none-eabi");
   auto CI = cantFail(CB.CreateCpp());
-  EXPECT_EQ(CI->getTargetOpts().Triple, "armv6-none-unknown-eabi");
+  EXPECT_EQ(CI->getTargetOpts().Triple, "armv6-unknown-none-eabi");
   cleanupRemappedFileBuffers(*CI);
 }
 
diff --git a/llvm/lib/TargetParser/Triple.cpp b/llvm/lib/TargetParser/Triple.cpp
index 2c5aee3dfb2f..f3f244c814e7 100644
--- a/llvm/lib/TargetParser/Triple.cpp
+++ b/llvm/lib/TargetParser/Triple.cpp
@@ -1151,6 +1151,12 @@ std::string Triple::normalize(StringRef Str) {
     }
   }
 
+  // If "none" is in the middle component in a three-component triple, treat it
+  // as the OS (Components[2]) instead of the vendor (Components[1]).
+  if (Found[0] && !Found[1] && !Found[2] && Found[3] &&
+      Components[1] == "none" && Components[2].empty())
+    std::swap(Components[1], Components[2]);
+
   // Replace empty components with "unknown" value.
   for (StringRef &C : Components)
     if (C.empty())
diff --git a/llvm/unittests/TargetParser/TripleTest.cpp b/llvm/unittests/TargetParser/TripleTest.cpp
index 0fa7e7690389..b8f5fbd87407 100644
--- a/llvm/unittests/TargetParser/TripleTest.cpp
+++ b/llvm/unittests/TargetParser/TripleTest.cpp
@@ -1237,7 +1237,7 @@ TEST(TripleTest, Normalization) {
             Triple::normalize("i386-redhat-linux")); // i386-redhat-linux-gnu
   EXPECT_EQ("i686-unknown-linux",
             Triple::normalize("i686-linux")); // i686-pc-linux-gnu
-  EXPECT_EQ("arm-none-unknown-eabi",
+  EXPECT_EQ("arm-unknown-none-eabi",
             Triple::normalize("arm-none-eabi")); // arm-none-eabi
   EXPECT_EQ("ve-unknown-linux",
             Triple::normalize("ve-linux")); // ve-linux