stage2: make use of `llvm.Context` in LLVM backend

This for example allows for multiple LLVM instances to run in parallel.

Also rename some functions in llvm_bindings.zig.

Fixes #7688

2 files changed, 74 insertions, 66 deletions

diff --git a/src/llvm_backend.zig b/src/llvm_backend.zig
index 2e7615d6ed..2bac4523c9 100644
--- a/src/llvm_backend.zig
+++ b/src/llvm_backend.zig
@@ -140,6 +140,7 @@ pub fn targetTriple(allocator: *Allocator, target: std.Target) ![:0]u8 {
 pub const LLVMIRModule = struct {
     module: *Module,
     llvm_module: *const llvm.Module,
+    context: *const llvm.Context,
     target_machine: *const llvm.TargetMachine,
     builder: *const llvm.Builder,
 
@@ -181,19 +182,22 @@ pub const LLVMIRModule = struct {
         const object_path = try o_directory.join(gpa, &[_][]const u8{obj_basename});
         errdefer gpa.free(object_path);
 
+        const context = llvm.Context.create();
+        errdefer context.dispose();
+
         initializeLLVMTargets();
 
         const root_nameZ = try gpa.dupeZ(u8, options.root_name);
         defer gpa.free(root_nameZ);
-        const llvm_module = llvm.Module.createWithName(root_nameZ.ptr);
-        errdefer llvm_module.disposeModule();
+        const llvm_module = llvm.Module.createWithName(root_nameZ.ptr, context);
+        errdefer llvm_module.dispose();
 
         const llvm_target_triple = try targetTriple(gpa, options.target);
         defer gpa.free(llvm_target_triple);
 
         var error_message: [*:0]const u8 = undefined;
         var target: *const llvm.Target = undefined;
-        if (llvm.Target.getTargetFromTriple(llvm_target_triple.ptr, &target, &error_message)) {
+        if (llvm.Target.getFromTriple(llvm_target_triple.ptr, &target, &error_message)) {
             defer llvm.disposeMessage(error_message);
 
             const stderr = std.io.getStdErr().outStream();
@@ -213,7 +217,7 @@ pub const LLVMIRModule = struct {
         }
 
         const opt_level: llvm.CodeGenOptLevel = if (options.optimize_mode == .Debug) .None else .Aggressive;
-        const target_machine = llvm.TargetMachine.createTargetMachine(
+        const target_machine = llvm.TargetMachine.create(
             target,
             llvm_target_triple.ptr,
             "",
@@ -222,14 +226,15 @@ pub const LLVMIRModule = struct {
             .Static,
             .Default,
         );
-        errdefer target_machine.disposeTargetMachine();
+        errdefer target_machine.dispose();
 
-        const builder = llvm.Builder.createBuilder();
-        errdefer builder.disposeBuilder();
+        const builder = context.createBuilder();
+        errdefer builder.dispose();
 
         self.* = .{
             .module = options.module.?,
             .llvm_module = llvm_module,
+            .context = context,
             .target_machine = target_machine,
             .builder = builder,
             .object_path = object_path,
@@ -239,9 +244,10 @@ pub const LLVMIRModule = struct {
     }
 
     pub fn deinit(self: *LLVMIRModule, allocator: *Allocator) void {
-        self.builder.disposeBuilder();
-        self.target_machine.disposeTargetMachine();
-        self.llvm_module.disposeModule();
+        self.builder.dispose();
+        self.target_machine.dispose();
+        self.llvm_module.dispose();
+        self.context.dispose();
 
         self.func_inst_table.deinit(self.gpa);
         self.gpa.free(self.object_path);
@@ -271,7 +277,7 @@ pub const LLVMIRModule = struct {
             // verifyModule always allocs the error_message even if there is no error
             defer llvm.disposeMessage(error_message);
 
-            if (self.llvm_module.verifyModule(.ReturnStatus, &error_message)) {
+            if (self.llvm_module.verify(.ReturnStatus, &error_message)) {
                 const stderr = std.io.getStdErr().outStream();
                 try stderr.print("broken LLVM module found: {s}\nThis is a bug in the Zig compiler.", .{error_message});
                 return error.BrokenLLVMModule;
@@ -340,7 +346,7 @@ pub const LLVMIRModule = struct {
                 bb.deleteBasicBlock();
             }
 
-            self.entry_block = llvm_func.appendBasicBlock("Entry");
+            self.entry_block = self.context.appendBasicBlock(llvm_func, "Entry");
             self.builder.positionBuilderAtEnd(self.entry_block);
             self.latest_alloca_inst = null;
 
@@ -606,7 +612,7 @@ pub const LLVMIRModule = struct {
                         return self.fail(src, "TODO handle other sentinel values", .{});
                     } else false;
 
-                    return llvm.constString(payload.data.ptr, @intCast(c_uint, payload.data.len), !zero_sentinel);
+                    return self.context.constString(payload.data.ptr, @intCast(c_uint, payload.data.len), !zero_sentinel);
                 } else {
                     return self.fail(src, "TODO handle more array values", .{});
                 }
@@ -617,13 +623,13 @@ pub const LLVMIRModule = struct {
 
     fn getLLVMType(self: *LLVMIRModule, t: Type, src: usize) error{ OutOfMemory, CodegenFail }!*const llvm.Type {
         switch (t.zigTypeTag()) {
-            .Void => return llvm.voidType(),
-            .NoReturn => return llvm.voidType(),
+            .Void => return self.context.voidType(),
+            .NoReturn => return self.context.voidType(),
             .Int => {
                 const info = t.intInfo(self.module.getTarget());
-                return llvm.intType(info.bits);
+                return self.context.intType(info.bits);
             },
-            .Bool => return llvm.intType(1),
+            .Bool => return self.context.intType(1),
             .Pointer => {
                 if (t.isSlice()) {
                     return self.fail(src, "TODO: LLVM backend: implement slices", .{});
@@ -688,12 +694,25 @@ pub const LLVMIRModule = struct {
         const llvm_fn = self.llvm_module.addFunction(func.name, fn_type);
 
         if (return_type.tag() == .noreturn) {
-            llvm_fn.addFnAttr("noreturn");
+            self.addFnAttr(llvm_fn, "noreturn");
         }
 
         return llvm_fn;
     }
 
+    // Helper functions
+    fn addAttr(self: LLVMIRModule, val: *const llvm.Value, index: llvm.AttributeIndex, name: []const u8) void {
+        const kind_id = llvm.getEnumAttributeKindForName(name.ptr, name.len);
+        assert(kind_id != 0);
+        const llvm_attr = self.context.createEnumAttribute(kind_id, 0);
+        val.addAttributeAtIndex(index, llvm_attr);
+    }
+
+    fn addFnAttr(self: *LLVMIRModule, val: *const llvm.Value, attr_name: []const u8) void {
+        // TODO: improve this API, `addAttr(-1, attr_name)`
+        self.addAttr(val, std.math.maxInt(llvm.AttributeIndex), attr_name);
+    }
+
     pub fn fail(self: *LLVMIRModule, src: usize, comptime format: []const u8, args: anytype) error{ OutOfMemory, CodegenFail } {
         @setCold(true);
         assert(self.err_msg == null);
diff --git a/src/llvm_bindings.zig b/src/llvm_bindings.zig
index 4a3c37cef7..1af64e85f6 100644
--- a/src/llvm_bindings.zig
+++ b/src/llvm_bindings.zig
@@ -5,35 +5,44 @@ const std = @import("std");
 const assert = std.debug.assert;
 
 const LLVMBool = bool;
-pub const LLVMAttributeIndex = c_uint;
+pub const AttributeIndex = c_uint;
+
+/// Make sure to use the *InContext functions instead of the global ones.
+pub const Context = opaque {
+    pub const create = LLVMContextCreate;
+    extern fn LLVMContextCreate() *const Context;
+
+    pub const dispose = LLVMContextDispose;
+    extern fn LLVMContextDispose(C: *const Context) void;
+
+    pub const createEnumAttribute = LLVMCreateEnumAttribute;
+    extern fn LLVMCreateEnumAttribute(*const Context, KindID: c_uint, Val: u64) *const Attribute;
+
+    pub const intType = LLVMIntTypeInContext;
+    extern fn LLVMIntTypeInContext(C: *const Context, NumBits: c_uint) *const Type;
+
+    pub const voidType = LLVMVoidTypeInContext;
+    extern fn LLVMVoidTypeInContext(C: *const Context) *const Type;
+
+    pub const constString = LLVMConstStringInContext;
+    extern fn LLVMConstStringInContext(C: *const Context, Str: [*]const u8, Length: c_uint, DontNullTerminate: LLVMBool) *const Value;
+
+    pub const appendBasicBlock = LLVMAppendBasicBlockInContext;
+    extern fn LLVMAppendBasicBlockInContext(C: *const Context, Fn: *const Value, Name: [*:0]const u8) *const BasicBlock;
+
+    pub const createBuilder = LLVMCreateBuilderInContext;
+    extern fn LLVMCreateBuilderInContext(C: *const Context) *const Builder;
+};
 
 pub const Value = opaque {
     pub const addAttributeAtIndex = LLVMAddAttributeAtIndex;
-    extern fn LLVMAddAttributeAtIndex(*const Value, Idx: LLVMAttributeIndex, A: *const Attribute) void;
-
-    pub const appendBasicBlock = LLVMAppendBasicBlock;
-    extern fn LLVMAppendBasicBlock(Fn: *const Value, Name: [*:0]const u8) *const BasicBlock;
+    extern fn LLVMAddAttributeAtIndex(*const Value, Idx: AttributeIndex, A: *const Attribute) void;
 
     pub const getFirstBasicBlock = LLVMGetFirstBasicBlock;
     extern fn LLVMGetFirstBasicBlock(Fn: *const Value) ?*const BasicBlock;
 
     pub const getNextInstruction = LLVMGetNextInstruction;
     extern fn LLVMGetNextInstruction(Inst: *const Value) ?*const Value;
-
-    // Helper functions
-    // TODO: Do we want to put these functions here? It allows for convienient function calls
-    //       on Value: llvm_fn.addFnAttr("noreturn")
-    fn addAttr(val: *const Value, index: LLVMAttributeIndex, name: []const u8) void {
-        const kind_id = getEnumAttributeKindForName(name.ptr, name.len);
-        assert(kind_id != 0);
-        const llvm_attr = Context.getGlobal().createEnumAttribute(kind_id, 0);
-        val.addAttributeAtIndex(index, llvm_attr);
-    }
-
-    pub fn addFnAttr(val: *const Value, attr_name: []const u8) void {
-        // TODO: improve this API, `addAttr(-1, attr_name)`
-        val.addAttr(std.math.maxInt(LLVMAttributeIndex), attr_name);
-    }
 };
 
 pub const Type = opaque {
@@ -63,13 +72,13 @@ pub const Type = opaque {
 };
 
 pub const Module = opaque {
-    pub const createWithName = LLVMModuleCreateWithName;
-    extern fn LLVMModuleCreateWithName(ModuleID: [*:0]const u8) *const Module;
+    pub const createWithName = LLVMModuleCreateWithNameInContext;
+    extern fn LLVMModuleCreateWithNameInContext(ModuleID: [*:0]const u8, C: *const Context) *const Module;
 
-    pub const disposeModule = LLVMDisposeModule;
+    pub const dispose = LLVMDisposeModule;
     extern fn LLVMDisposeModule(*const Module) void;
 
-    pub const verifyModule = LLVMVerifyModule;
+    pub const verify = LLVMVerifyModule;
     extern fn LLVMVerifyModule(*const Module, Action: VerifierFailureAction, OutMessage: *[*:0]const u8) LLVMBool;
 
     pub const addFunction = LLVMAddFunction;
@@ -106,15 +115,9 @@ pub const VerifierFailureAction = extern enum {
 pub const constNeg = LLVMConstNeg;
 extern fn LLVMConstNeg(ConstantVal: *const Value) *const Value;
 
-pub const constString = LLVMConstString;
-extern fn LLVMConstString(Str: [*]const u8, Length: c_uint, DontNullTerminate: LLVMBool) *const Value;
-
 pub const setInitializer = LLVMSetInitializer;
 extern fn LLVMSetInitializer(GlobalVar: *const Value, ConstantVal: *const Value) void;
 
-pub const voidType = LLVMVoidType;
-extern fn LLVMVoidType() *const Type;
-
 pub const getParam = LLVMGetParam;
 extern fn LLVMGetParam(Fn: *const Value, Index: c_uint) *const Value;
 
@@ -123,22 +126,8 @@ extern fn LLVMGetEnumAttributeKindForName(Name: [*]const u8, SLen: usize) c_uint
 
 pub const Attribute = opaque {};
 
-pub const Context = opaque {
-    pub const createEnumAttribute = LLVMCreateEnumAttribute;
-    extern fn LLVMCreateEnumAttribute(*const Context, KindID: c_uint, Val: u64) *const Attribute;
-
-    pub const getGlobal = LLVMGetGlobalContext;
-    extern fn LLVMGetGlobalContext() *const Context;
-};
-
-pub const intType = LLVMIntType;
-extern fn LLVMIntType(NumBits: c_uint) *const Type;
-
 pub const Builder = opaque {
-    pub const createBuilder = LLVMCreateBuilder;
-    extern fn LLVMCreateBuilder() *const Builder;
-
-    pub const disposeBuilder = LLVMDisposeBuilder;
+    pub const dispose = LLVMDisposeBuilder;
     extern fn LLVMDisposeBuilder(Builder: *const Builder) void;
 
     pub const positionBuilder = LLVMPositionBuilder;
@@ -208,7 +197,7 @@ pub const BasicBlock = opaque {
 };
 
 pub const TargetMachine = opaque {
-    pub const createTargetMachine = LLVMCreateTargetMachine;
+    pub const create = LLVMCreateTargetMachine;
     extern fn LLVMCreateTargetMachine(
         T: *const Target,
         Triple: [*:0]const u8,
@@ -219,7 +208,7 @@ pub const TargetMachine = opaque {
         CodeModel: CodeMode,
     ) *const TargetMachine;
 
-    pub const disposeTargetMachine = LLVMDisposeTargetMachine;
+    pub const dispose = LLVMDisposeTargetMachine;
     extern fn LLVMDisposeTargetMachine(T: *const TargetMachine) void;
 
     pub const emitToFile = LLVMTargetMachineEmitToFile;
@@ -259,7 +248,7 @@ pub const CodeGenFileType = extern enum {
 };
 
 pub const Target = opaque {
-    pub const getTargetFromTriple = LLVMGetTargetFromTriple;
+    pub const getFromTriple = LLVMGetTargetFromTriple;
     extern fn LLVMGetTargetFromTriple(Triple: [*:0]const u8, T: **const Target, ErrorMessage: *[*:0]const u8) LLVMBool;
 };