[clang] [llvm] [LoongArch] Support amcas[_db].{b/h/w/d} instructions. (PR #114189)

[WÁNG Xuěruì via cfe-commits]

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@@ -0,0 +1,30 @@
+/// Test -m[no]lamcas options.
+
+// RUN: %clang --target=loongarch64 -mlamcas -fsyntax-only %s -### 2>&1 | \
+// RUN:     FileCheck %s --check-prefix=CC1-LAMCAS
+// RUN: %clang --target=loongarch64 -mno-lamcas -fsyntax-only %s -### 2>&1 | \
+// RUN:     FileCheck %s --check-prefix=CC1-NO-LAMCAS
+// RUN: %clang --target=loongarch64 -mno-lamcas -mlamcas -fsyntax-only %s -### 2>&1 | \
+// RUN:     FileCheck %s --check-prefix=CC1-LAMCAS
+// RUN: %clang --target=loongarch64  -mlamcas -mno-lamcas -fsyntax-only %s -### 2>&1 | \
+// RUN:     FileCheck %s --check-prefix=CC1-NO-LAMCAS
+
+// RUN: %clang --target=loongarch64 -mlamcas -S -emit-llvm %s -o - | \
+// RUN: FileCheck %s --check-prefix=IR-LAMCAS
+// RUN: %clang --target=loongarch64 -mno-lamcas -S -emit-llvm %s -o - | \
+// RUN: FileCheck %s --check-prefix=IR-NO-LAMCAS
+// RUN: %clang --target=loongarch64 -mno-lamcas -mlamcas -S -emit-llvm %s -o - | \
+// RUN: FileCheck %s --check-prefix=IR-LAMCAS
+// RUN: %clang --target=loongarch64 -mlamcas -mno-lamcas -S -emit-llvm %s -o - | \
+// RUN: FileCheck %s --check-prefix=IR-NO-LAMCAS
+
+
+// CC1-LAMCAS: "-target-feature" "+lamcas"
+// CC1-NO-LAMCAS: "-target-feature" "-lamcas"
+
+// IR-LAMCAS: attributes #[[#]] ={{.*}}"target-features"="{{(.*,)?}}+lamcas{{(,.*)?}}"
+// IR-NO-LAMCAS: attributes #[[#]] ={{.*}}"target-features"="{{(.*,)?}}-lamcas{{(,.*)?}}"
+
+int foo(void) {
+  return 42;
+}
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xen0n wrote:

missing trailing newline

https://github.com/llvm/llvm-project/pull/114189