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self-hosted: generate LLVM IR for simple function

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This commit is contained in:
Andrew Kelley
2018-07-15 00:04:12 -04:00
parent 28c3d4809b
commit 363f4facea
8 changed files with 412 additions and 11 deletions
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158
src-self-hosted/codegen.zig
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@@ -8,6 +8,7 @@ const ir = @import("ir.zig");
const Value = @import("value.zig").Value;
const Type = @import("type.zig").Type;
const event = std.event;
const assert = std.debug.assert;
pub async fn renderToLlvm(comp: *Compilation, fn_val: *Value.Fn, code: *ir.Code) !void {
fn_val.base.ref();
@@ -35,9 +36,23 @@ pub async fn renderToLlvm(comp: *Compilation, fn_val: *Value.Fn, code: *ir.Code)
try renderToLlvmModule(&ofile, fn_val, code);
// TODO module level assembly
//if (buf_len(&g->global_asm) != 0) {
// LLVMSetModuleInlineAsm(g->module, buf_ptr(&g->global_asm));
//}
// TODO
//ZigLLVMDIBuilderFinalize(g->dbuilder);
if (comp.verbose_llvm_ir) {
llvm.DumpModule(ofile.module);
}
// verify the llvm module when safety is on
if (std.debug.runtime_safety) {
var error_ptr: ?[*]u8 = null;
_ = llvm.VerifyModule(ofile.module, llvm.AbortProcessAction, &error_ptr);
}
}
pub const ObjectFile = struct {
@@ -55,5 +70,146 @@ pub const ObjectFile = struct {
pub fn renderToLlvmModule(ofile: *ObjectFile, fn_val: *Value.Fn, code: *ir.Code) !void {
// TODO audit more of codegen.cpp:fn_llvm_value and port more logic
const llvm_fn_type = try fn_val.base.typeof.getLlvmType(ofile);
const llvm_fn = llvm.AddFunction(ofile.module, fn_val.symbol_name.ptr(), llvm_fn_type);
const llvm_fn = llvm.AddFunction(
ofile.module,
fn_val.symbol_name.ptr(),
llvm_fn_type,
) orelse return error.OutOfMemory;
const want_fn_safety = fn_val.block_scope.safety.get(ofile.comp);
if (want_fn_safety and ofile.comp.haveLibC()) {
try addLLVMFnAttr(ofile, llvm_fn, "sspstrong");
try addLLVMFnAttrStr(ofile, llvm_fn, "stack-protector-buffer-size", "4");
}
// TODO
//if (fn_val.align_stack) |align_stack| {
// try addLLVMFnAttrInt(ofile, llvm_fn, "alignstack", align_stack);
//}
const fn_type = fn_val.base.typeof.cast(Type.Fn).?;
try addLLVMFnAttr(ofile, llvm_fn, "nounwind");
//add_uwtable_attr(g, fn_table_entry->llvm_value);
try addLLVMFnAttr(ofile, llvm_fn, "nobuiltin");
//if (g->build_mode == BuildModeDebug && fn_table_entry->fn_inline != FnInlineAlways) {
// ZigLLVMAddFunctionAttr(fn_table_entry->llvm_value, "no-frame-pointer-elim", "true");
// ZigLLVMAddFunctionAttr(fn_table_entry->llvm_value, "no-frame-pointer-elim-non-leaf", nullptr);
//}
//if (fn_table_entry->section_name) {
// LLVMSetSection(fn_table_entry->llvm_value, buf_ptr(fn_table_entry->section_name));
//}
//if (fn_table_entry->align_bytes > 0) {
// LLVMSetAlignment(fn_table_entry->llvm_value, (unsigned)fn_table_entry->align_bytes);
//} else {
// // We'd like to set the best alignment for the function here, but on Darwin LLVM gives
// // "Cannot getTypeInfo() on a type that is unsized!" assertion failure when calling
// // any of the functions for getting alignment. Not specifying the alignment should
// // use the ABI alignment, which is fine.
//}
//if (!type_has_bits(return_type)) {
// // nothing to do
//} else if (type_is_codegen_pointer(return_type)) {
// addLLVMAttr(fn_table_entry->llvm_value, 0, "nonnull");
//} else if (handle_is_ptr(return_type) &&
// calling_convention_does_first_arg_return(fn_type->data.fn.fn_type_id.cc))
//{
// addLLVMArgAttr(fn_table_entry->llvm_value, 0, "sret");
// addLLVMArgAttr(fn_table_entry->llvm_value, 0, "nonnull");
//}
// TODO set parameter attributes
// TODO
//uint32_t err_ret_trace_arg_index = get_err_ret_trace_arg_index(g, fn_table_entry);
//if (err_ret_trace_arg_index != UINT32_MAX) {
// addLLVMArgAttr(fn_table_entry->llvm_value, (unsigned)err_ret_trace_arg_index, "nonnull");
//}
const cur_ret_ptr = if (fn_type.return_type.handleIsPtr()) llvm.GetParam(llvm_fn, 0) else null;
// build all basic blocks
for (code.basic_block_list.toSlice()) |bb| {
bb.llvm_block = llvm.AppendBasicBlockInContext(
ofile.context,
llvm_fn,
bb.name_hint,
) orelse return error.OutOfMemory;
}
const entry_bb = code.basic_block_list.at(0);
llvm.PositionBuilderAtEnd(ofile.builder, entry_bb.llvm_block);
llvm.ClearCurrentDebugLocation(ofile.builder);
// TODO set up error return tracing
// TODO allocate temporary stack values
// TODO create debug variable declarations for variables and allocate all local variables
// TODO finishing error return trace setup. we have to do this after all the allocas.
// TODO create debug variable declarations for parameters
for (code.basic_block_list.toSlice()) |current_block| {
llvm.PositionBuilderAtEnd(ofile.builder, current_block.llvm_block);
for (current_block.instruction_list.toSlice()) |instruction| {
if (instruction.ref_count == 0 and !instruction.hasSideEffects()) continue;
instruction.llvm_value = try instruction.render(ofile, fn_val);
}
current_block.llvm_exit_block = llvm.GetInsertBlock(ofile.builder);
}
}
fn addLLVMAttr(
ofile: *ObjectFile,
val: llvm.ValueRef,
attr_index: llvm.AttributeIndex,
attr_name: []const u8,
) !void {
const kind_id = llvm.GetEnumAttributeKindForName(attr_name.ptr, attr_name.len);
assert(kind_id != 0);
const llvm_attr = llvm.CreateEnumAttribute(ofile.context, kind_id, 0) orelse return error.OutOfMemory;
llvm.AddAttributeAtIndex(val, attr_index, llvm_attr);
}
fn addLLVMAttrStr(
ofile: *ObjectFile,
val: llvm.ValueRef,
attr_index: llvm.AttributeIndex,
attr_name: []const u8,
attr_val: []const u8,
) !void {
const llvm_attr = llvm.CreateStringAttribute(
ofile.context,
attr_name.ptr,
@intCast(c_uint, attr_name.len),
attr_val.ptr,
@intCast(c_uint, attr_val.len),
) orelse return error.OutOfMemory;
llvm.AddAttributeAtIndex(val, attr_index, llvm_attr);
}
fn addLLVMAttrInt(
val: llvm.ValueRef,
attr_index: llvm.AttributeIndex,
attr_name: []const u8,
attr_val: u64,
) !void {
const kind_id = llvm.GetEnumAttributeKindForName(attr_name.ptr, attr_name.len);
assert(kind_id != 0);
const llvm_attr = llvm.CreateEnumAttribute(ofile.context, kind_id, attr_val) orelse return error.OutOfMemory;
llvm.AddAttributeAtIndex(val, attr_index, llvm_attr);
}
fn addLLVMFnAttr(ofile: *ObjectFile, fn_val: llvm.ValueRef, attr_name: []const u8) !void {
return addLLVMAttr(ofile, fn_val, @maxValue(llvm.AttributeIndex), attr_name);
}
fn addLLVMFnAttrStr(ofile: *ObjectFile, fn_val: llvm.ValueRef, attr_name: []const u8, attr_val: []const u8) !void {
return addLLVMAttrStr(ofile, fn_val, @maxValue(llvm.AttributeIndex), attr_name, attr_val);
}
fn addLLVMFnAttrInt(ofile: *ObjectFile, fn_val: llvm.ValueRef, attr_name: []const u8, attr_val: u64) !void {
return addLLVMAttrInt(ofile, fn_val, @maxValue(llvm.AttributeIndex), attr_name, attr_val);
}