Support LLVM 20 (#15412)

Tested using version `20.1.0~++20250202013302+1eb7f4e6b461-1~exp1~20250202013426.11` from the official Apt repository, a few days beyond the RC1 release.

Since Crystal has never used the MMX register type during LLVM IR generation, no major changes are needed.

src/llvm/enums.cr

@@ -249,7 +249,12 @@ module LLVM
       Pointer
       Vector
       Metadata
-      X86_MMX
+      X86_MMX # deleted in LLVM 20
+      Token
+      ScalableVector
+      BFloat
+      X86_AMX
+      TargetExt
     end
   end
 

src/llvm/ext/llvm-versions.txt

@@ -1 +1 @@
-19.1 18.1 17.0 16.0 15.0 14.0 13.0 12.0 11.1 11.0 10.0 9.0 8.0
+20.1 19.1 18.1 17.0 16.0 15.0 14.0 13.0 12.0 11.1 11.0 10.0 9.0 8.0

src/llvm/function_collection.cr

@@ -30,7 +30,13 @@ struct LLVM::FunctionCollection
   end
 
   def []?(name)
-    func = LibLLVM.get_named_function(@mod, name)
+    func =
+      {% if LibLLVM::IS_LT_200 %}
+        LibLLVM.get_named_function(@mod, name)
+      {% else %}
+        LibLLVM.get_named_function_with_length(@mod, name, name.bytesize)
+      {% end %}
+
     func ? Function.new(func) : nil
   end
 

src/llvm/global_collection.cr

@@ -9,7 +9,13 @@ struct LLVM::GlobalCollection
   end
 
   def []?(name)
-    global = LibLLVM.get_named_global(@mod, name)
+    global =
+      {% if LibLLVM::IS_LT_200 %}
+        LibLLVM.get_named_global(@mod, name)
+      {% else %}
+        LibLLVM.get_named_global_with_length(@mod, name, name.bytesize)
+      {% end %}
+
     global ? Value.new(global) : nil
   end
 

src/llvm/lib_llvm.cr

@@ -71,6 +71,7 @@
     IS_LT_170 = {{compare_versions(LibLLVM::VERSION, "17.0.0") < 0}}
     IS_LT_180 = {{compare_versions(LibLLVM::VERSION, "18.0.0") < 0}}
     IS_LT_190 = {{compare_versions(LibLLVM::VERSION, "19.0.0") < 0}}
+    IS_LT_200 = {{compare_versions(LibLLVM::VERSION, "20.0.0") < 0}}
   end
 {% end %}
 

src/llvm/lib_llvm/core.cr

@@ -50,7 +50,11 @@ lib LibLLVM
   fun get_module_context = LLVMGetModuleContext(m : ModuleRef) : ContextRef
 
   fun add_function = LLVMAddFunction(m : ModuleRef, name : Char*, function_ty : TypeRef) : ValueRef
-  fun get_named_function = LLVMGetNamedFunction(m : ModuleRef, name : Char*) : ValueRef
+  {% if LibLLVM::IS_LT_200 %}
+    fun get_named_function = LLVMGetNamedFunction(m : ModuleRef, name : Char*) : ValueRef
+  {% else %}
+    fun get_named_function_with_length = LLVMGetNamedFunctionWithLength(m : ModuleRef, name : Char*, length : SizeT) : ValueRef
+  {% end %}
   fun get_first_function = LLVMGetFirstFunction(m : ModuleRef) : ValueRef
   fun get_next_function = LLVMGetNextFunction(fn : ValueRef) : ValueRef
 
@@ -144,7 +148,11 @@ lib LibLLVM
   fun set_alignment = LLVMSetAlignment(v : ValueRef, bytes : UInt)
 
   fun add_global = LLVMAddGlobal(m : ModuleRef, ty : TypeRef, name : Char*) : ValueRef
-  fun get_named_global = LLVMGetNamedGlobal(m : ModuleRef, name : Char*) : ValueRef
+  {% if LibLLVM::IS_LT_200 %}
+    fun get_named_global = LLVMGetNamedGlobal(m : ModuleRef, name : Char*) : ValueRef
+  {% else %}
+    fun get_named_global_with_length = LLVMGetNamedGlobalWithLength(m : ModuleRef, name : Char*, length : SizeT) : ValueRef
+  {% end %}
   fun get_initializer = LLVMGetInitializer(global_var : ValueRef) : ValueRef
   fun set_initializer = LLVMSetInitializer(global_var : ValueRef, constant_val : ValueRef)
   fun is_thread_local = LLVMIsThreadLocal(global_var : ValueRef) : Bool