add PDF rendering performance harness

1 files changed, 34 insertions, 0 deletions

diff --git a/build.zig b/build.zig
index 126f86dc..95592c80 100644
--- a/build.zig
+++ b/build.zig
@@ -50,8 +50,11 @@ pub fn build(b: *std.Build) void {
     // JavaScript owns the loop and IO; HTML/CSS own rendering.
     const web_step = b.step("web", "build the DOM browser shell into zig-out/web (-Dplatform=web -Dtarget=wasm32-freestanding -Ddump=<dump.zon>)");
     const mupdf_check = b.step("mupdf-check", "compile, link, render, and search docs/design.pdf with MuPDF");
+    const pdf_bench_step = b.step("pdf-bench", "benchmark real MuPDF page rendering (-- [--json] [--reps N] [--warmup N] [--path FILE] [--page N] [--pages N])");
     if (!enable_mupdf)
         mupdf_check.dependOn(&b.addFail("mupdf-check is unavailable with -Dmupdf=false").step);
+    if (!enable_mupdf)
+        pdf_bench_step.dependOn(&b.addFail("pdf-bench is unavailable with -Dmupdf=false").step);
 
     // Web LOOK has a tiny read-only source filesystem. Generate one Zig module
     // on the host from every tracked .zig path + its current working-tree
@@ -374,6 +377,37 @@ pub fn build(b: *std.Build) void {
                 .target = target,
                 .pdf = b.path("docs/design.pdf"),
             }));
+
+            // A headless renderer benchmark with its own ReleaseFast wrapper
+            // module. Reusing root_mod's Debug-mode MuPDF import here would
+            // benchmark Zig safety checks around optimized C rather than the
+            // production-cost boundary the scoreboard is meant to expose.
+            const pdf_bench_mod = b.createModule(.{
+                .target = target,
+                .optimize = .ReleaseFast,
+                .root_source_file = b.path("src/pdf.zig"),
+                .link_libc = true,
+            });
+            mupdf.linkTo(pdf_bench_mod);
+            pdf_bench_mod.addIncludePath(b.path("src"));
+            pdf_bench_mod.addCSourceFile(.{
+                .file = b.path("src/pdf_bridge.c"),
+                .flags = &.{"-std=gnu11"},
+            });
+            const pdf_bench = b.addExecutable(.{
+                .name = "pardes-pdf-bench",
+                .root_module = b.createModule(.{
+                    .target = target,
+                    .optimize = .ReleaseFast,
+                    .root_source_file = b.path("test/pdf_bench.zig"),
+                    .link_libc = true,
+                }),
+            });
+            pdf_bench.root_module.addImport("mupdf", pdf_bench_mod);
+            const run_pdf_bench = b.addRunArtifact(pdf_bench);
+            if (b.args) |args| run_pdf_bench.addArgs(args);
+            run_pdf_bench.setCwd(b.path("."));
+            pdf_bench_step.dependOn(&run_pdf_bench.step);
         }
     }