Commit 0784d389844a127248bb724352ce7101bc49784c | zig

author	Matthew Lugg <mlugg@mlugg.co.uk> 2024-02-04 17:46:04+00:00
committer	Matthew Lugg <mlugg@mlugg.co.uk> 2024-02-04 19:17:20+00:00
log	0784d389844a127248bb724352ce7101bc49784c
tree	731c64a78aa6118823bb3579c679fea5a31b5900
parent	0d8207c29236bf731f7d3bad189beb3a1e1b1d0c
signature	Commit is signed but in an unrecognized format.

compiler: lock incremental dependency tracking behind --debug-incremental

This logic (currently) has a non-trivial cost (particularly in terms of
peak RSS) for tracking dependencies. Until incremental compilation is in
use in the wild, it doesn't make sense for users to pay that cost.

4 files changed, 36 insertions(+), 21 deletions(-)

src/Compilation.zig+3

src/Module.zig+2

...	@@ -3139,6 +3139,8 @@ fn markDeclDependenciesPotentiallyOutdated(zcu: *Zcu, decl_index: Decl.Index) !v	...	@@ -3139,6 +3139,8 @@ fn markDeclDependenciesPotentiallyOutdated(zcu: *Zcu, decl_index: Decl.Index) !v
3139	}	3139	}
3140		3140
3141	pub fn findOutdatedToAnalyze(zcu: *Zcu) Allocator.Error!?InternPool.Depender {	3141	pub fn findOutdatedToAnalyze(zcu: *Zcu) Allocator.Error!?InternPool.Depender {
		3142	if (!zcu.comp.debug_incremental) return null;
		3143
3142	if (zcu.outdated.count() == 0 and zcu.potentially_outdated.count() == 0) {	3144	if (zcu.outdated.count() == 0 and zcu.potentially_outdated.count() == 0) {
3143	log.debug("findOutdatedToAnalyze: no outdated depender", .{});	3145	log.debug("findOutdatedToAnalyze: no outdated depender", .{});
3144	return null;	3146	return null;

src/Sema.zig+30-21

 @@ -2788,11 +2788,13 @@ fn zirStructDecl(
     new_decl.owns_tv = true;
     errdefer mod.abortAnonDecl(new_decl_index);
-    try ip.addDependency(
+    if (sema.mod.comp.debug_incremental) {
-        sema.gpa,
+        try ip.addDependency(
-        InternPool.Depender.wrap(.{ .decl = new_decl_index }),
+            sema.gpa,
-        .{ .src_hash = try ip.trackZir(sema.gpa, block.getFileScope(mod), inst) },
+            InternPool.Depender.wrap(.{ .decl = new_decl_index }),
-    );
+            .{ .src_hash = try ip.trackZir(sema.gpa, block.getFileScope(mod), inst) },
+        );
+    }
     const new_namespace_index = try mod.createNamespace(.{
         .parent = block.namespace.toOptional(),
 @@ -2978,11 +2980,13 @@ fn zirEnumDecl(
     new_decl.owns_tv = true;
     errdefer if (!done) mod.abortAnonDecl(new_decl_index);
-    try mod.intern_pool.addDependency(
+    if (sema.mod.comp.debug_incremental) {
-        sema.gpa,
+        try mod.intern_pool.addDependency(
-        InternPool.Depender.wrap(.{ .decl = new_decl_index }),
+            sema.gpa,
-        .{ .src_hash = try mod.intern_pool.trackZir(sema.gpa, block.getFileScope(mod), inst) },
+            InternPool.Depender.wrap(.{ .decl = new_decl_index }),
-    );
+            .{ .src_hash = try mod.intern_pool.trackZir(sema.gpa, block.getFileScope(mod), inst) },
+        );
+    }
     const new_namespace_index = try mod.createNamespace(.{
         .parent = block.namespace.toOptional(),
 @@ -3237,11 +3241,13 @@ fn zirUnionDecl(
     new_decl.owns_tv = true;
     errdefer mod.abortAnonDecl(new_decl_index);
-    try mod.intern_pool.addDependency(
+    if (sema.mod.comp.debug_incremental) {
-        sema.gpa,
+        try mod.intern_pool.addDependency(
-        InternPool.Depender.wrap(.{ .decl = new_decl_index }),
+            sema.gpa,
-        .{ .src_hash = try mod.intern_pool.trackZir(sema.gpa, block.getFileScope(mod), inst) },
+            InternPool.Depender.wrap(.{ .decl = new_decl_index }),
-    );
+            .{ .src_hash = try mod.intern_pool.trackZir(sema.gpa, block.getFileScope(mod), inst) },
+        );
+    }
     const new_namespace_index = try mod.createNamespace(.{
         .parent = block.namespace.toOptional(),
 @@ -3336,11 +3342,13 @@ fn zirOpaqueDecl(
     new_decl.owns_tv = true;
     errdefer mod.abortAnonDecl(new_decl_index);
-    try mod.intern_pool.addDependency(
+    if (sema.mod.comp.debug_incremental) {
-        sema.gpa,
+        try mod.intern_pool.addDependency(
-        InternPool.Depender.wrap(.{ .decl = new_decl_index }),
+            sema.gpa,
-        .{ .src_hash = try mod.intern_pool.trackZir(sema.gpa, block.getFileScope(mod), inst) },
+            InternPool.Depender.wrap(.{ .decl = new_decl_index }),
-    );
+            .{ .src_hash = try mod.intern_pool.trackZir(sema.gpa, block.getFileScope(mod), inst) },
+        );
+    }
     const new_namespace_index = try mod.createNamespace(.{
         .parent = block.namespace.toOptional(),
 @@ -32435,7 +32443,7 @@ fn analyzeDeclRefInner(sema: *Sema, decl_index: InternPool.DeclIndex, analyze_fn
     const decl = mod.declPtr(decl_index);
     const decl_tv = try decl.typedValue();
-    // TODO: if this is a `decl_ref`, only depend on decl type
+    // TODO: if this is a `decl_ref` of a non-variable decl, only depend on decl type
     try sema.declareDependency(.{ .decl_val = decl_index });
     const ptr_ty = try sema.ptrType(.{
         .child = decl_tv.ty.toIntern(),
 @@ -38925,6 +38933,7 @@ fn ptrType(sema: *Sema, info: InternPool.Key.PtrType) CompileError!Type {
 }
 pub fn declareDependency(sema: *Sema, dependee: InternPool.Dependee) !void {
+    if (!sema.mod.comp.debug_incremental) return;
     const depender = InternPool.Depender.wrap(
         if (sema.owner_func_index != .none)
             .{ .func = sema.owner_func_index }

src/main.zig+1

...	@@ -3255,6 +3255,7 @@ fn buildOutputType(	...	@@ -3255,6 +3255,7 @@ fn buildOutputType(
3255	.cache_mode = cache_mode,	3255	.cache_mode = cache_mode,
3256	.subsystem = subsystem,	3256	.subsystem = subsystem,
3257	.debug_compile_errors = debug_compile_errors,	3257	.debug_compile_errors = debug_compile_errors,
		3258	.debug_incremental = debug_incremental,
3258	.enable_link_snapshots = enable_link_snapshots,	3259	.enable_link_snapshots = enable_link_snapshots,
3259	.install_name = install_name,	3260	.install_name = install_name,
3260	.entitlements = entitlements,	3261	.entitlements = entitlements,

...	@@ -156,6 +156,7 @@ time_report: bool,	...	@@ -156,6 +156,7 @@ time_report: bool,
156	stack_report: bool,	156	stack_report: bool,
157	debug_compiler_runtime_libs: bool,	157	debug_compiler_runtime_libs: bool,
158	debug_compile_errors: bool,	158	debug_compile_errors: bool,
		159	debug_incremental: bool,
159	job_queued_compiler_rt_lib: bool = false,	160	job_queued_compiler_rt_lib: bool = false,
160	job_queued_compiler_rt_obj: bool = false,	161	job_queued_compiler_rt_obj: bool = false,
161	job_queued_update_builtin_zig: bool,	162	job_queued_update_builtin_zig: bool,
...	@@ -1079,6 +1080,7 @@ pub const CreateOptions = struct {	...	@@ -1079,6 +1080,7 @@ pub const CreateOptions = struct {
1079	verbose_llvm_cpu_features: bool = false,	1080	verbose_llvm_cpu_features: bool = false,
1080	debug_compiler_runtime_libs: bool = false,	1081	debug_compiler_runtime_libs: bool = false,
1081	debug_compile_errors: bool = false,	1082	debug_compile_errors: bool = false,
		1083	debug_incremental: bool = false,
1082	/// Normally when you create a `Compilation`, Zig will automatically build	1084	/// Normally when you create a `Compilation`, Zig will automatically build
1083	/// and link in required dependencies, such as compiler-rt and libc. When	1085	/// and link in required dependencies, such as compiler-rt and libc. When
1084	/// building such dependencies themselves, this flag must be set to avoid	1086	/// building such dependencies themselves, this flag must be set to avoid
...	@@ -1508,6 +1510,7 @@ pub fn create(gpa: Allocator, arena: Allocator, options: CreateOptions) !*Compil	...	@@ -1508,6 +1510,7 @@ pub fn create(gpa: Allocator, arena: Allocator, options: CreateOptions) !*Compil
1508	.test_name_prefix = options.test_name_prefix,	1510	.test_name_prefix = options.test_name_prefix,
1509	.debug_compiler_runtime_libs = options.debug_compiler_runtime_libs,	1511	.debug_compiler_runtime_libs = options.debug_compiler_runtime_libs,
1510	.debug_compile_errors = options.debug_compile_errors,	1512	.debug_compile_errors = options.debug_compile_errors,
		1513	.debug_incremental = options.debug_incremental,
1511	.libcxx_abi_version = options.libcxx_abi_version,	1514	.libcxx_abi_version = options.libcxx_abi_version,
1512	.root_name = root_name,	1515	.root_name = root_name,
1513	.sysroot = sysroot,	1516	.sysroot = sysroot,