ZJIT: Move jit.rs to ruby.rs and create a shared crate jit

* ruby.rs should hold the main entrypoint to YJIT and ZJIT
* The crate jit will hold code shared between them

Cargo.lock

@@ -62,11 +62,7 @@ dependencies = [
 
 [[package]]
 name = "jit"
-version = "0.0.0"
-dependencies = [
- "yjit",
- "zjit",
-]
+version = "0.1.0"
 
 [[package]]
 name = "lazy_static"
@@ -86,6 +82,14 @@ version = "1.21.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "42f5e15c9953c5e4ccceeb2e7382a716482c34515315f7b03532b8b4e8393d2d"
 
+[[package]]
+name = "ruby"
+version = "0.0.0"
+dependencies = [
+ "yjit",
+ "zjit",
+]
+
 [[package]]
 name = "shlex"
 version = "1.3.0"
@@ -176,6 +180,7 @@ name = "yjit"
 version = "0.1.0"
 dependencies = [
  "capstone",
+ "jit",
 ]
 
 [[package]]
@@ -184,4 +189,5 @@ version = "0.0.1"
 dependencies = [
  "capstone",
  "insta",
+ "jit",
 ]

Cargo.toml

@@ -3,10 +3,10 @@
 # TODO(alan) notes about rust version requirements. Undecided yet.
 
 [workspace]
-members = ["zjit", "yjit"]
+members = ["zjit", "yjit", "jit"]
 
 [package]
-name = "jit"
+name = "ruby"
 version = "0.0.0"
 edition = "2024"
 rust-version = "1.85.0"
@@ -18,7 +18,7 @@ zjit = { path = "zjit", optional = true }
 
 [lib]
 crate-type = ["staticlib"]
-path = "jit.rs"
+path = "ruby.rs"
 
 [features]
 disasm = ["yjit?/disasm", "zjit?/disasm"]

configure.ac

@@ -4019,9 +4019,9 @@ AS_IF([test x"$JIT_CARGO_SUPPORT" != "xno" -o \( x"$YJIT_SUPPORT" != "xno" -a x"
     ])
     CARGO_BUILD_ARGS="--profile ${JIT_CARGO_SUPPORT} --features ${rb_cargo_features}"
     AS_IF([test "${JIT_CARGO_SUPPORT}" = "dev"], [
-        RUST_LIB="target/debug/libjit.a"
+        RUST_LIB="target/debug/libruby.a"
     ], [
-        RUST_LIB="target/${JIT_CARGO_SUPPORT}/libjit.a"
+        RUST_LIB="target/${JIT_CARGO_SUPPORT}/libruby.a"
     ])
 ])
 

defs/jit.mk

@@ -17,7 +17,7 @@ CARGO_VERBOSE = $(CARGO_VERBOSE_$(V))
 #    ld: warning: object file (target/debug/libjit.a(<libcapstone object>)) was built for
 #    newer macOS version (15.2) than being linked (15.0)
 # This limits us to an older set of macOS API in the rust code, but we don't use any.
-$(RUST_LIB): $(srcdir)/jit.rs
+$(RUST_LIB): $(srcdir)/ruby.rs
 	$(Q)if [ '$(ZJIT_SUPPORT)' != no -a '$(YJIT_SUPPORT)' != no ]; then \
 	    echo 'building YJIT and ZJIT ($(JIT_CARGO_SUPPORT:yes=release) mode)'; \
 	elif [ '$(ZJIT_SUPPORT)' != no ]; then \

jit/Cargo.toml

@@ -0,0 +1,6 @@
+[package]
+name = "jit"
+version = "0.1.0"
+edition = "2024"
+
+[dependencies]

jit/src/lib.rs

@@ -0,0 +1,37 @@
+//! Shared code between YJIT and ZJIT.
+
+use std::sync::atomic::{AtomicUsize, Ordering};
+use std::alloc::{GlobalAlloc, Layout, System};
+
+#[global_allocator]
+pub static GLOBAL_ALLOCATOR: StatsAlloc = StatsAlloc { alloc_size: AtomicUsize::new(0) };
+
+pub struct StatsAlloc {
+    pub alloc_size: AtomicUsize,
+}
+
+unsafe impl GlobalAlloc for StatsAlloc {
+    unsafe fn alloc(&self, layout: Layout) -> *mut u8 {
+        self.alloc_size.fetch_add(layout.size(), Ordering::SeqCst);
+        unsafe { System.alloc(layout) }
+    }
+
+    unsafe fn dealloc(&self, ptr: *mut u8, layout: Layout) {
+        self.alloc_size.fetch_sub(layout.size(), Ordering::SeqCst);
+        unsafe { System.dealloc(ptr, layout) }
+    }
+
+    unsafe fn alloc_zeroed(&self, layout: Layout) -> *mut u8 {
+        self.alloc_size.fetch_add(layout.size(), Ordering::SeqCst);
+        unsafe { System.alloc_zeroed(layout) }
+    }
+
+    unsafe fn realloc(&self, ptr: *mut u8, layout: Layout, new_size: usize) -> *mut u8 {
+        if new_size > layout.size() {
+            self.alloc_size.fetch_add(new_size - layout.size(), Ordering::SeqCst);
+        } else if new_size < layout.size() {
+            self.alloc_size.fetch_sub(layout.size() - new_size, Ordering::SeqCst);
+        }
+        unsafe { System.realloc(ptr, layout, new_size) }
+    }
+}

yjit/Cargo.toml

@@ -13,6 +13,7 @@ publish = false         # Don't publish to crates.io
 # No required dependencies to simplify build process. TODO: Link to yet to be
 # written rationale. Optional For development and testing purposes
 capstone = { version = "0.13.0", optional = true }
+jit = { version = "0.1.0", path = "../jit" }
 
 # NOTE: Development builds select a set of these via configure.ac
 # For debugging, `make V=1` shows exact cargo invocation.

zjit/Cargo.toml

@@ -9,6 +9,7 @@ publish = false         # Don't publish to crates.io
 # No required dependencies to simplify build process. TODO: Link to yet to be
 # written rationale. Optional For development and testing purposes
 capstone = { version = "0.13.0", optional = true }
+jit = { version = "0.1.0", path = "../jit" }
 
 [dev-dependencies]
 insta = "1.43.1"