rustc_codegen_llvm: Name major version of LLVM

It makes LLVM version comparison clearer.

Author: a4lg

compiler/rustc_codegen_llvm/src/llvm_util.rs

@@ -228,6 +228,7 @@ pub(crate) fn to_llvm_features<'a>(sess: &Session, s: &'a str) -> Option<LLVMFea
     } else {
         &*sess.target.arch
     };
+    let (major, _, _) = get_version();
     match (arch, s) {
         ("x86", "sse4.2") => Some(LLVMFeature::with_dependencies(
             "sse4.2",
@@ -247,8 +248,8 @@ pub(crate) fn to_llvm_features<'a>(sess: &Session, s: &'a str) -> Option<LLVMFea
         ("aarch64", "paca") => Some(LLVMFeature::new("pauth")),
         ("aarch64", "pacg") => Some(LLVMFeature::new("pauth")),
         // Before LLVM 20 those two features were packaged together as b16b16
-        ("aarch64", "sve-b16b16") if get_version().0 < 20 => Some(LLVMFeature::new("b16b16")),
-        ("aarch64", "sme-b16b16") if get_version().0 < 20 => Some(LLVMFeature::new("b16b16")),
+        ("aarch64", "sve-b16b16") if major < 20 => Some(LLVMFeature::new("b16b16")),
+        ("aarch64", "sme-b16b16") if major < 20 => Some(LLVMFeature::new("b16b16")),
         ("aarch64", "flagm2") => Some(LLVMFeature::new("altnzcv")),
         // Rust ties fp and neon together.
         ("aarch64", "neon") => Some(LLVMFeature::with_dependencies(
@@ -263,31 +264,27 @@ pub(crate) fn to_llvm_features<'a>(sess: &Session, s: &'a str) -> Option<LLVMFea
         ("aarch64", "fpmr") => None, // only existed in 18
         ("arm", "fp16") => Some(LLVMFeature::new("fullfp16")),
         // NVPTX targets added in LLVM 20
-        ("nvptx64", "sm_100") if get_version().0 < 20 => None,
-        ("nvptx64", "sm_100a") if get_version().0 < 20 => None,
-        ("nvptx64", "sm_101") if get_version().0 < 20 => None,
-        ("nvptx64", "sm_101a") if get_version().0 < 20 => None,
-        ("nvptx64", "sm_120") if get_version().0 < 20 => None,
-        ("nvptx64", "sm_120a") if get_version().0 < 20 => None,
-        ("nvptx64", "ptx86") if get_version().0 < 20 => None,
-        ("nvptx64", "ptx87") if get_version().0 < 20 => None,
+        ("nvptx64", "sm_100") if major < 20 => None,
+        ("nvptx64", "sm_100a") if major < 20 => None,
+        ("nvptx64", "sm_101") if major < 20 => None,
+        ("nvptx64", "sm_101a") if major < 20 => None,
+        ("nvptx64", "sm_120") if major < 20 => None,
+        ("nvptx64", "sm_120a") if major < 20 => None,
+        ("nvptx64", "ptx86") if major < 20 => None,
+        ("nvptx64", "ptx87") if major < 20 => None,
         // Filter out features that are not supported by the current LLVM version
-        ("loongarch64", "div32" | "lam-bh" | "lamcas" | "ld-seq-sa" | "scq")
-            if get_version().0 < 20 =>
-        {
-            None
-        }
-        ("loongarch32" | "loongarch64", "32s") if get_version().0 < 21 => None,
+        ("loongarch64", "div32" | "lam-bh" | "lamcas" | "ld-seq-sa" | "scq") if major < 20 => None,
+        ("loongarch32" | "loongarch64", "32s") if major < 21 => None,
         // Filter out features that are not supported by the current LLVM version
-        ("riscv32" | "riscv64", "zacas" | "rva23u64" | "supm") if get_version().0 < 20 => None,
+        ("riscv32" | "riscv64", "zacas" | "rva23u64" | "supm") if major < 20 => None,
         (
             "s390x",
             "message-security-assist-extension12"
             | "concurrent-functions"
             | "miscellaneous-extensions-4"
             | "vector-enhancements-3"
             | "vector-packed-decimal-enhancement-3",
-        ) if get_version().0 < 20 => None,
+        ) if major < 20 => None,
         // Enable the evex512 target feature if an avx512 target feature is enabled.
         ("x86", s) if s.starts_with("avx512") => Some(LLVMFeature::with_dependencies(
             s,
@@ -301,18 +298,18 @@ pub(crate) fn to_llvm_features<'a>(sess: &Session, s: &'a str) -> Option<LLVMFea
         // https://github.com/llvm/llvm-project/blob/llvmorg-19.1.0/llvm/lib/Target/Sparc/MCTargetDesc/SparcELFObjectWriter.cpp#L27-L28
         // Before LLVM 19, there was no `v8plus` feature and `v9` means "SPARC-V9 instruction available".
         // https://github.com/llvm/llvm-project/blob/llvmorg-18.1.0/llvm/lib/Target/Sparc/MCTargetDesc/SparcELFObjectWriter.cpp#L26
-        ("sparc", "v8plus") if get_version().0 == 19 => Some(LLVMFeature::new("v9")),
+        ("sparc", "v8plus") if major == 19 => Some(LLVMFeature::new("v9")),
         ("powerpc", "power8-crypto") => Some(LLVMFeature::new("crypto")),
         // These new `amx` variants and `movrs` were introduced in LLVM20
         ("x86", "amx-avx512" | "amx-fp8" | "amx-movrs" | "amx-tf32" | "amx-transpose")
-            if get_version().0 < 20 =>
+            if major < 20 =>
         {
             None
         }
-        ("x86", "movrs") if get_version().0 < 20 => None,
+        ("x86", "movrs") if major < 20 => None,
         ("x86", "avx10.1") => Some(LLVMFeature::new("avx10.1-512")),
-        ("x86", "avx10.2") if get_version().0 < 20 => None,
-        ("x86", "avx10.2") if get_version().0 >= 20 => Some(LLVMFeature::new("avx10.2-512")),
+        ("x86", "avx10.2") if major < 20 => None,
+        ("x86", "avx10.2") if major >= 20 => Some(LLVMFeature::new("avx10.2-512")),
         ("x86", "apxf") => Some(LLVMFeature::with_dependencies(
             "egpr",
             smallvec![