Commit 031f23117dadd84b1e7189ee5b0f712eeb23ca1e | zig

author	Andrew Kelley <andrew@ziglang.org> 2024-02-26 04:03:40-08:00
committer	GitHub <noreply@github.com> 2024-02-26 04:03:40-08:00
log	031f23117dadd84b1e7189ee5b0f712eeb23ca1e
tree	38a5e91df49ef36abd5f1579f8d9bef8124ef69f
parent	032c2ee9bc1fae507be776c118cd03d28c865edc
parent	73a16d440ba7968bab11acddc2129f05e09daa0d
signature	Signed by PGP key B5690EEEBB952194

Merge pull request #19083 from antlilja/llvm-blockinfo

LLVM reduce size of emitted bitcode

3 files changed, 67 insertions(+), 28 deletions(-)

src
- codegen
  - llvm
    Builder.zig
    bitcode_writer.zig
    ir.zig

src/codegen/llvm/Builder.zig+38-11

 @@ -13114,7 +13114,7 @@ pub fn toBitcode(self: *Builder, allocator: Allocator) bitcode_writer.Error![]co
         // TYPE_BLOCK
         {
-            var type_block = try module_block.enterSubBlock(ir.Type);
+            var type_block = try module_block.enterSubBlock(ir.Type, true);
             try type_block.writeAbbrev(ir.Type.NumEntry{ .num = @intCast(self.type_items.items.len) });
 @@ -13221,7 +13221,7 @@ pub fn toBitcode(self: *Builder, allocator: Allocator) bitcode_writer.Error![]co
         {
             const ParamattrGroup = ir.ParamattrGroup;
-            var paramattr_group_block = try module_block.enterSubBlock(ParamattrGroup);
+            var paramattr_group_block = try module_block.enterSubBlock(ParamattrGroup, true);
             for (self.function_attributes_set.keys()) |func_attributes| {
                 for (func_attributes.slice(self), 0..) |attributes, i| {
 @@ -13424,7 +13424,7 @@ pub fn toBitcode(self: *Builder, allocator: Allocator) bitcode_writer.Error![]co
         // PARAMATTR_BLOCK
         {
             const Paramattr = ir.Paramattr;
-            var paramattr_block = try module_block.enterSubBlock(Paramattr);
+            var paramattr_block = try module_block.enterSubBlock(Paramattr, true);
             for (self.function_attributes_set.keys()) |func_attributes| {
                 const func_attributes_slice = func_attributes.slice(self);
 @@ -13627,7 +13627,7 @@ pub fn toBitcode(self: *Builder, allocator: Allocator) bitcode_writer.Error![]co
         // CONSTANTS_BLOCK
         {
             const Constants = ir.Constants;
-            var constants_block = try module_block.enterSubBlock(Constants);
+            var constants_block = try module_block.enterSubBlock(Constants, true);
             var current_type: Type = .none;
             const tags = self.constant_items.items(.tag);
 @@ -13953,7 +13953,7 @@ pub fn toBitcode(self: *Builder, allocator: Allocator) bitcode_writer.Error![]co
         // METADATA_KIND_BLOCK
         if (!self.strip) {
             const MetadataKindBlock = ir.MetadataKindBlock;
-            var metadata_kind_block = try module_block.enterSubBlock(MetadataKindBlock);
+            var metadata_kind_block = try module_block.enterSubBlock(MetadataKindBlock, true);
             inline for (@typeInfo(ir.MetadataKind).Enum.fields) |field| {
                 try metadata_kind_block.writeAbbrev(MetadataKindBlock.Kind{
 @@ -14006,7 +14006,7 @@ pub fn toBitcode(self: *Builder, allocator: Allocator) bitcode_writer.Error![]co
         // METADATA_BLOCK
         if (!self.strip) {
             const MetadataBlock = ir.MetadataBlock;
-            var metadata_block = try module_block.enterSubBlock(MetadataBlock);
+            var metadata_block = try module_block.enterSubBlock(MetadataBlock, true);
             const MetadataBlockWriter = @TypeOf(metadata_block);
 @@ -14411,6 +14411,34 @@ pub fn toBitcode(self: *Builder, allocator: Allocator) bitcode_writer.Error![]co
             try metadata_block.end();
         }
+        // Block info
+        {
+            const BlockInfo = ir.BlockInfo;
+            var block_info_block = try module_block.enterSubBlock(BlockInfo, true);
+            try block_info_block.writeUnabbrev(BlockInfo.set_block_id, &.{ir.FunctionBlock.id});
+            inline for (ir.FunctionBlock.abbrevs) |abbrev| {
+                try block_info_block.defineAbbrev(&abbrev.ops);
+            }
+            try block_info_block.writeUnabbrev(BlockInfo.set_block_id, &.{ir.FunctionValueSymbolTable.id});
+            inline for (ir.FunctionValueSymbolTable.abbrevs) |abbrev| {
+                try block_info_block.defineAbbrev(&abbrev.ops);
+            }
+            try block_info_block.writeUnabbrev(BlockInfo.set_block_id, &.{ir.FunctionMetadataBlock.id});
+            inline for (ir.FunctionMetadataBlock.abbrevs) |abbrev| {
+                try block_info_block.defineAbbrev(&abbrev.ops);
+            }
+            try block_info_block.writeUnabbrev(BlockInfo.set_block_id, &.{ir.MetadataAttachmentBlock.id});
+            inline for (ir.MetadataAttachmentBlock.abbrevs) |abbrev| {
+                try block_info_block.defineAbbrev(&abbrev.ops);
+            }
+            try block_info_block.end();
+        }
         // FUNCTION_BLOCKS
         {
             const FunctionAdapter = struct {
 @@ -14500,7 +14528,7 @@ pub fn toBitcode(self: *Builder, allocator: Allocator) bitcode_writer.Error![]co
                 if (func.instructions.len == 0) continue;
-                var function_block = try module_block.enterSubBlock(FunctionBlock);
+                var function_block = try module_block.enterSubBlock(FunctionBlock, false);
                 try function_block.writeAbbrev(FunctionBlock.DeclareBlocks{ .num_blocks = func.blocks.len });
 @@ -14509,7 +14537,7 @@ pub fn toBitcode(self: *Builder, allocator: Allocator) bitcode_writer.Error![]co
                 // Emit function level metadata block
                 if (!func.strip and func.debug_values.len > 0) {
                     const MetadataBlock = ir.FunctionMetadataBlock;
-                    var metadata_block = try function_block.enterSubBlock(MetadataBlock);
+                    var metadata_block = try function_block.enterSubBlock(MetadataBlock, false);
                     for (func.debug_values) |value| {
                         try metadata_block.writeAbbrev(MetadataBlock.Value{
 @@ -14978,7 +15006,6 @@ pub fn toBitcode(self: *Builder, allocator: Allocator) bitcode_writer.Error![]co
                                         .column = location.column,
                                         .scope = @enumFromInt(metadata_adapter.getMetadataIndex(location.scope)),
                                         .inlined_at = @enumFromInt(metadata_adapter.getMetadataIndex(location.inlined_at)),
-                                        .is_implicit = false,
                                     });
                                     has_location = true;
                                 },
 @@ -14995,7 +15022,7 @@ pub fn toBitcode(self: *Builder, allocator: Allocator) bitcode_writer.Error![]co
                 if (!func.strip) {
                     const ValueSymbolTable = ir.FunctionValueSymbolTable;
-                    var value_symtab_block = try function_block.enterSubBlock(ValueSymbolTable);
+                    var value_symtab_block = try function_block.enterSubBlock(ValueSymbolTable, false);
                     for (func.blocks, 0..) |block, block_index| {
                         const name = block.instruction.name(&func);
 @@ -15020,7 +15047,7 @@ pub fn toBitcode(self: *Builder, allocator: Allocator) bitcode_writer.Error![]co
                     if (dbg == .none) break :blk;
                     const MetadataAttachmentBlock = ir.MetadataAttachmentBlock;
-                    var metadata_attach_block = try function_block.enterSubBlock(MetadataAttachmentBlock);
+                    var metadata_attach_block = try function_block.enterSubBlock(MetadataAttachmentBlock, false);
                     try metadata_attach_block.writeAbbrev(MetadataAttachmentBlock.AttachmentSingle{
                         .kind = ir.MetadataKind.dbg,

src/codegen/llvm/bitcode_writer.zig+16-11

 @@ -148,7 +148,7 @@ pub fn BitcodeWriter(comptime types: []const type) type {
         }
         pub fn enterTopBlock(self: *BcWriter, comptime SubBlock: type) Error!BlockWriter(SubBlock) {
-            return BlockWriter(SubBlock).init(self, 2);
+            return BlockWriter(SubBlock).init(self, 2, true);
         }
         fn BlockWriter(comptime Block: type) type {
 @@ -164,7 +164,7 @@ pub fn BitcodeWriter(comptime types: []const type) type {
                 start: usize,
                 bitcode: *BcWriter,
-                pub fn init(bitcode: *BcWriter, comptime parent_abbrev_len: u6) Error!Self {
+                pub fn init(bitcode: *BcWriter, comptime parent_abbrev_len: u6, comptime define_abbrevs: bool) Error!Self {
                     try bitcode.writeBits(1, parent_abbrev_len);
                     try bitcode.writeVBR(Block.id, 8);
                     try bitcode.writeVBR(abbrev_len, 4);
 @@ -174,19 +174,23 @@ pub fn BitcodeWriter(comptime types: []const type) type {
                     const start = bitcode.length();
                     try bitcode.writeBits(0, 32);
-                    // Predefine all block abbrevs
+                    var self = Self{
-                    inline for (Block.abbrevs) |Abbrev| {
-                        try defineAbbrev(bitcode, &Abbrev.ops);
-                    }
-                    return .{
                         .start = start,
                         .bitcode = bitcode,
                     };
+                    // Predefine all block abbrevs
+                    if (define_abbrevs) {
+                        inline for (Block.abbrevs) |Abbrev| {
+                            try self.defineAbbrev(&Abbrev.ops);
+                        }
+                    }
+                    return self;
                 }
-                pub fn enterSubBlock(self: Self, comptime SubBlock: type) Error!BlockWriter(SubBlock) {
+                pub fn enterSubBlock(self: Self, comptime SubBlock: type, comptime define_abbrevs: bool) Error!BlockWriter(SubBlock) {
-                    return BlockWriter(SubBlock).init(self.bitcode, abbrev_len);
+                    return BlockWriter(SubBlock).init(self.bitcode, abbrev_len, define_abbrevs);
                 }
                 pub fn end(self: *Self) Error!void {
 @@ -291,7 +295,8 @@ pub fn BitcodeWriter(comptime types: []const type) type {
                     }
                 }
-                fn defineAbbrev(bitcode: *BcWriter, comptime ops: []const AbbrevOp) Error!void {
+                pub fn defineAbbrev(self: *Self, comptime ops: []const AbbrevOp) Error!void {
+                    const bitcode = self.bitcode;
                     try bitcode.writeBits(2, abbrev_len);
                     // ops.len is not accurate because arrays are actually two ops

src/codegen/llvm/ir.zig+13-6

 @@ -186,6 +186,14 @@ pub const Module = struct {
     };
 };
+pub const BlockInfo = struct {
+    pub const id = 0;
+    pub const set_block_id = 1;
+    pub const abbrevs = [_]type{};
+};
 pub const Type = struct {
     pub const id = 17;
 @@ -1583,17 +1591,16 @@ pub const FunctionBlock = struct {
     pub const DebugLoc = struct {
         pub const ops = [_]AbbrevOp{
             .{ .literal = 35 },
-            .{ .fixed = 32 },
+            LineAbbrev,
-            .{ .fixed = 32 },
+            ColumnAbbrev,
-            .{ .fixed = 32 },
+            MetadataAbbrev,
-            .{ .fixed = 32 },
+            MetadataAbbrev,
-            .{ .fixed = 1 },
+            .{ .literal = 0 },
         };
         line: u32,
         column: u32,
         scope: Builder.Metadata,
         inlined_at: Builder.Metadata,
-        is_implicit: bool,
     };
     pub const DebugLocAgain = struct {