diff --git a/clang/lib/Driver/ToolChains/Arch/LoongArch.cpp b/clang/lib/Driver/ToolChains/Arch/LoongArch.cpp
--- a/clang/lib/Driver/ToolChains/Arch/LoongArch.cpp
+++ b/clang/lib/Driver/ToolChains/Arch/LoongArch.cpp
@@ -54,7 +54,28 @@
   }
 
   // Choose a default based on the triple.
-  return IsLA32 ? "ilp32d" : "lp64d";
+  // Honor the explicit ABI modifier suffix in triple's environment part if
+  // present, falling back to {ILP32,LP64}D otherwise.
+  switch (Triple.getEnvironment()) {
+  case llvm::Triple::GNUSF:
+    return IsLA32 ? "ilp32s" : "lp64s";
+  case llvm::Triple::GNUF32:
+    return IsLA32 ? "ilp32f" : "lp64f";
+  case llvm::Triple::GNUF64:
+    // This was originally permitted (and indeed the canonical way) to
+    // represent the {ILP32,LP64}D ABIs, but in Feb 2023 Loongson decided to
+    // drop the explicit suffix in favor of unmarked `-gnu` for the
+    // "general-purpose" ABIs, among other non-technical reasons.
+    //
+    // The spec change did not mention whether existing usages of "gnuf64"
+    // shall remain valid or not, so we are going to continue recognizing it
+    // for some time, until it is clear that everyone else has migrated away
+    // from it.
+    [[fallthrough]];
+  case llvm::Triple::GNU:
+  default:
+    return IsLA32 ? "ilp32d" : "lp64d";
+  }
 }
 
 void loongarch::getLoongArchTargetFeatures(const Driver &D,
diff --git a/clang/lib/Driver/ToolChains/Linux.cpp b/clang/lib/Driver/ToolChains/Linux.cpp
--- a/clang/lib/Driver/ToolChains/Linux.cpp
+++ b/clang/lib/Driver/ToolChains/Linux.cpp
@@ -86,6 +86,39 @@
   case llvm::Triple::aarch64_be:
     return "aarch64_be-linux-gnu";
 
+  case llvm::Triple::loongarch64: {
+    const char *Libc;
+    const char *FPFlavor;
+
+    if (TargetTriple.isGNUEnvironment()) {
+      Libc = "gnu";
+    } else if (TargetTriple.isMusl()) {
+      Libc = "musl";
+    } else {
+      return TargetTriple.str();
+    }
+
+    switch (TargetEnvironment) {
+    default:
+      return TargetTriple.str();
+    case llvm::Triple::GNUSF:
+      FPFlavor = "sf";
+      break;
+    case llvm::Triple::GNUF32:
+      FPFlavor = "f32";
+      break;
+    case llvm::Triple::GNU:
+    case llvm::Triple::GNUF64:
+      // This was going to be "f64" in an earlier Toolchain Conventions
+      // revision, but starting from Feb 2023 the F64 ABI variants are
+      // unmarked in their canonical forms.
+      FPFlavor = "";
+      break;
+    }
+
+    return (Twine("loongarch64-linux-") + Libc + FPFlavor).str();
+  }
+
   case llvm::Triple::m68k:
     return "m68k-linux-gnu";
 
diff --git a/clang/test/Driver/Inputs/debian_loong64_tree/usr/include/c++/13/backward/.keep b/clang/test/Driver/Inputs/debian_loong64_tree/usr/include/c++/13/backward/.keep
new file mode 100644
diff --git a/clang/test/Driver/Inputs/debian_loong64_tree/usr/include/loongarch64-linux-gnu/c++/.keep b/clang/test/Driver/Inputs/debian_loong64_tree/usr/include/loongarch64-linux-gnu/c++/.keep
new file mode 100644
diff --git a/clang/test/Driver/Inputs/debian_loong64_tree/usr/lib/gcc/loongarch64-linux-gnu/13/crtbegin.o b/clang/test/Driver/Inputs/debian_loong64_tree/usr/lib/gcc/loongarch64-linux-gnu/13/crtbegin.o
new file mode 100644
diff --git a/clang/test/Driver/Inputs/debian_loong64_tree/usr/lib/gcc/loongarch64-linux-gnu/13/crtend.o b/clang/test/Driver/Inputs/debian_loong64_tree/usr/lib/gcc/loongarch64-linux-gnu/13/crtend.o
new file mode 100644
diff --git a/clang/test/Driver/Inputs/debian_loong64_tree/usr/lib/gcc/loongarch64-linux-gnu/13/include/.keep b/clang/test/Driver/Inputs/debian_loong64_tree/usr/lib/gcc/loongarch64-linux-gnu/13/include/.keep
new file mode 100644
diff --git a/clang/test/Driver/Inputs/debian_loong64_tree/usr/lib/loongarch64-linux-gnu/crt1.o b/clang/test/Driver/Inputs/debian_loong64_tree/usr/lib/loongarch64-linux-gnu/crt1.o
new file mode 100644
diff --git a/clang/test/Driver/Inputs/debian_loong64_tree/usr/lib/loongarch64-linux-gnu/crti.o b/clang/test/Driver/Inputs/debian_loong64_tree/usr/lib/loongarch64-linux-gnu/crti.o
new file mode 100644
diff --git a/clang/test/Driver/Inputs/debian_loong64_tree/usr/lib/loongarch64-linux-gnu/crtn.o b/clang/test/Driver/Inputs/debian_loong64_tree/usr/lib/loongarch64-linux-gnu/crtn.o
new file mode 100644
diff --git a/clang/test/Driver/linux-header-search.cpp b/clang/test/Driver/linux-header-search.cpp
--- a/clang/test/Driver/linux-header-search.cpp
+++ b/clang/test/Driver/linux-header-search.cpp
@@ -244,6 +244,32 @@
 // CHECK-GENTOO-4-9-X-32: "-internal-externc-isystem" "[[SYSROOT]]/include"
 // CHECK-GENTOO-4-9-X-32: "-internal-externc-isystem" "[[SYSROOT]]/usr/include"
 //
+// Check header search on Debian loong64
+// RUN: %clang -### %s -fsyntax-only 2>&1 \
+// RUN:     --target=loongarch64-unknown-linux-gnu -stdlib=libstdc++ \
+// RUN:     --sysroot=%S/Inputs/debian_loong64_tree \
+// RUN:     --gcc-toolchain="" \
+// RUN:   | FileCheck --check-prefix=CHECK-LOONG64-GNU %s
+//
+// Check that "-gnuf64" is seen as "-gnu" for loong64.
+// RUN: %clang -### %s -fsyntax-only 2>&1 \
+// RUN:     --target=loongarch64-unknown-linux-gnuf64 -stdlib=libstdc++ \
+// RUN:     --sysroot=%S/Inputs/debian_loong64_tree \
+// RUN:     --gcc-toolchain="" \
+// RUN:   | FileCheck --check-prefix=CHECK-LOONG64-GNU %s
+// CHECK-LOONG64-GNU: "-cc1"
+// CHECK-LOONG64-GNU: "-resource-dir" "[[RESOURCE_DIR:[^"]+]]"
+// CHECK-LOONG64-GNU: "-isysroot" "[[SYSROOT:[^"]+]]"
+// CHECK-LOONG64-GNU: "-internal-isystem" "[[SYSROOT]]/usr/lib/gcc/loongarch64-linux-gnu/13/../../../../include/c++/13"
+// CHECK-LOONG64-GNU: "-internal-isystem" "[[SYSROOT]]/usr/lib/gcc/loongarch64-linux-gnu/13/../../../../include/c++/13/loongarch64-linux-gnu"
+// CHECK-LOONG64-GNU: "-internal-isystem" "[[SYSROOT]]/usr/lib/gcc/loongarch64-linux-gnu/13/../../../../include/c++/13/backward"
+// CHECK-LOONG64-GNU: "-internal-isystem" "[[RESOURCE_DIR]]{{/|\\\\}}include"
+// CHECK-LOONG64-GNU: "-internal-isystem" "[[SYSROOT]]/usr/local/include"
+// CHECK-LOONG64-GNU: "-internal-isystem" "[[SYSROOT]]/usr/lib/gcc/loongarch64-linux-gnu/13/../../../../loongarch64-linux-gnu/include"
+// CHECK-LOONG64-GNU: "-internal-externc-isystem" "[[SYSROOT]]/usr/include/loongarch64-linux-gnu"
+// CHECK-LOONG64-GNU: "-internal-externc-isystem" "[[SYSROOT]]/include"
+// CHECK-LOONG64-GNU: "-internal-externc-isystem" "[[SYSROOT]]/usr/include"
+//
 // Check header search on Debian 6 / MIPS64
 // RUN: %clang -### %s -fsyntax-only 2>&1 \
 // RUN:     --target=mips64-unknown-linux-gnuabi64 -stdlib=libstdc++ \
diff --git a/clang/test/Driver/linux-ld.c b/clang/test/Driver/linux-ld.c
--- a/clang/test/Driver/linux-ld.c
+++ b/clang/test/Driver/linux-ld.c
@@ -830,6 +830,30 @@
 // CHECK-ARM-HF: "-dynamic-linker" "{{.*}}/lib/ld-linux-armhf.so.3"
 //
 // RUN: %clang -### %s -no-pie 2>&1 \
+// RUN:     --target=loongarch64-linux-gnu \
+// RUN:   | FileCheck --check-prefix=CHECK-LOONGARCH-LP64D %s
+// RUN: %clang -### %s -no-pie 2>&1 \
+// RUN:     --target=loongarch64-linux-gnuf64 \
+// RUN:   | FileCheck --check-prefix=CHECK-LOONGARCH-LP64D %s
+// CHECK-LOONGARCH-LP64D: "{{.*}}ld{{(.exe)?}}"
+// CHECK-LOONGARCH-LP64D: "-m" "elf64loongarch"
+// CHECK-LOONGARCH-LP64D: "-dynamic-linker" "{{.*}}/lib64/ld-linux-loongarch-lp64d.so.1"
+//
+// RUN: %clang -### %s -no-pie 2>&1 \
+// RUN:     --target=loongarch64-linux-gnuf32 \
+// RUN:   | FileCheck --check-prefix=CHECK-LOONGARCH-LP64F %s
+// CHECK-LOONGARCH-LP64F: "{{.*}}ld{{(.exe)?}}"
+// CHECK-LOONGARCH-LP64F: "-m" "elf64loongarch"
+// CHECK-LOONGARCH-LP64F: "-dynamic-linker" "{{.*}}/lib64/ld-linux-loongarch-lp64f.so.1"
+//
+// RUN: %clang -### %s -no-pie 2>&1 \
+// RUN:     --target=loongarch64-linux-gnusf \
+// RUN:   | FileCheck --check-prefix=CHECK-LOONGARCH-LP64S %s
+// CHECK-LOONGARCH-LP64S: "{{.*}}ld{{(.exe)?}}"
+// CHECK-LOONGARCH-LP64S: "-m" "elf64loongarch"
+// CHECK-LOONGARCH-LP64S: "-dynamic-linker" "{{.*}}/lib64/ld-linux-loongarch-lp64s.so.1"
+//
+// RUN: %clang -### %s -no-pie 2>&1 \
 // RUN:     --target=powerpc64-linux-gnu \
 // RUN:   | FileCheck --check-prefix=CHECK-PPC64 %s
 // CHECK-PPC64: "{{.*}}ld{{(.exe)?}}"
@@ -1311,6 +1335,29 @@
 // RUN:   | FileCheck --check-prefix=CHECK-ANDROID-PTHREAD-LINK %s
 // CHECK-ANDROID-PTHREAD-LINK-NOT: argument unused during compilation: '-pthread'
 //
+// Check linker invocation on a Debian LoongArch sysroot.
+// RUN: %clang -### %s -no-pie 2>&1 \
+// RUN:     --target=loongarch64-linux-gnu -rtlib=platform \
+// RUN:     --gcc-toolchain="" \
+// RUN:     --sysroot=%S/Inputs/debian_loong64_tree \
+// RUN:   | FileCheck --check-prefix=CHECK-DEBIAN-ML-LOONG64 %s
+//
+// Check that "-gnuf64" is seen as "-gnu" for loong64.
+// RUN: %clang -### %s -no-pie 2>&1 \
+// RUN:     --target=loongarch64-linux-gnuf64 -rtlib=platform \
+// RUN:     --gcc-toolchain="" \
+// RUN:     --sysroot=%S/Inputs/debian_loong64_tree \
+// RUN:   | FileCheck --check-prefix=CHECK-DEBIAN-ML-LOONG64 %s
+// CHECK-DEBIAN-ML-LOONG64: "{{.*}}ld{{(.exe)?}}" "--sysroot=[[SYSROOT:[^"]+]]"
+// CHECK-DEBIAN-ML-LOONG64: "[[SYSROOT]]/usr/lib/loongarch64-linux-gnu/crt1.o"
+// CHECK-DEBIAN-ML-LOONG64: "[[SYSROOT]]/usr/lib/loongarch64-linux-gnu/crti.o"
+// CHECK-DEBIAN-ML-LOONG64: "[[SYSROOT]]/usr/lib/gcc/loongarch64-linux-gnu/13/crtbegin.o"
+// CHECK-DEBIAN-ML-LOONG64: "-L[[SYSROOT]]/usr/lib/gcc/loongarch64-linux-gnu/13"
+// CHECK-DEBIAN-ML-LOONG64: "-L[[SYSROOT]]/usr/lib/loongarch64-linux-gnu"
+// CHECK-DEBIAN-ML-LOONG64: "-L[[SYSROOT]]/usr/lib"
+// CHECK-DEBIAN-ML-LOONG64: "[[SYSROOT]]/usr/lib/gcc/loongarch64-linux-gnu/13/crtend.o"
+// CHECK-DEBIAN-ML-LOONG64: "[[SYSROOT]]/usr/lib/loongarch64-linux-gnu/crtn.o"
+//
 // Check linker invocation on Debian 6 MIPS 32/64-bit.
 // RUN: %clang -### %s -no-pie 2>&1 \
 // RUN:     --target=mipsel-linux-gnu -rtlib=platform \
diff --git a/clang/test/Driver/loongarch-abi.c b/clang/test/Driver/loongarch-abi.c
--- a/clang/test/Driver/loongarch-abi.c
+++ b/clang/test/Driver/loongarch-abi.c
@@ -16,6 +16,34 @@
 // RUN: %clang --target=loongarch64-unknown-elf %s -fsyntax-only -### -mabi=lp64d 2>&1 \
 // RUN:   | FileCheck --check-prefix=LP64D %s
 
+// RUN: %clang --target=loongarch32-linux-gnusf %s -fsyntax-only -### 2>&1 \
+// RUN:   | FileCheck --check-prefix=ILP32S %s
+// RUN: %clang --target=loongarch32-linux-gnuf32 %s -fsyntax-only -### 2>&1 \
+// RUN:   | FileCheck --check-prefix=ILP32F %s
+// RUN: %clang --target=loongarch32-linux-gnuf64 %s -fsyntax-only -### 2>&1 \
+// RUN:   | FileCheck --check-prefix=ILP32D %s
+// RUN: %clang --target=loongarch32-linux-gnu %s -fsyntax-only -### 2>&1 \
+// RUN:   | FileCheck --check-prefix=ILP32D %s
+
+// RUN: %clang --target=loongarch64-linux-gnusf %s -fsyntax-only -### 2>&1 \
+// RUN:   | FileCheck --check-prefix=LP64S %s
+// RUN: %clang --target=loongarch64-linux-gnuf32 %s -fsyntax-only -### 2>&1 \
+// RUN:   | FileCheck --check-prefix=LP64F %s
+// RUN: %clang --target=loongarch64-linux-gnuf64 %s -fsyntax-only -### 2>&1 \
+// RUN:   | FileCheck --check-prefix=LP64D %s
+// RUN: %clang --target=loongarch64-linux-gnu %s -fsyntax-only -### 2>&1 \
+// RUN:   | FileCheck --check-prefix=LP64D %s
+
+// Check that -mabi prevails in case of conflicts with the triple-implied ABI.
+// RUN: %clang --target=loongarch32-linux-gnuf64 %s -fsyntax-only -### -mabi=ilp32s 2>&1 \
+// RUN:   | FileCheck --check-prefix=ILP32S %s
+// RUN: %clang --target=loongarch64-linux-gnuf64 %s -fsyntax-only -### -mabi=lp64s 2>&1 \
+// RUN:   | FileCheck --check-prefix=LP64S %s
+// RUN: %clang --target=loongarch32-linux-gnu %s -fsyntax-only -### -mabi=ilp32s 2>&1 \
+// RUN:   | FileCheck --check-prefix=ILP32S %s
+// RUN: %clang --target=loongarch64-linux-gnu %s -fsyntax-only -### -mabi=lp64s 2>&1 \
+// RUN:   | FileCheck --check-prefix=LP64S %s
+
 // ILP32S: "-target-abi" "ilp32s"
 // ILP32F: "-target-abi" "ilp32f"
 // ILP32D: "-target-abi" "ilp32d"