fix build (disable error-on-warnings), WIP multikernel support for nThreads specificaiton

Author: austinvhuang

CMakeLists.txt

@@ -9,7 +9,6 @@ set(CMAKE_EXPORT_COMPILE_COMMANDS ON) # export compile_commands.json to use with
 set(CMAKE_CXX_STANDARD 17)
 set(CMAKE_CXX_STANDARD_REQUIRED ON)
 
-
 option(USE_LOCAL_LIBS "Use local libraries instead of fetching from the internet" OFF)
 
 # Define paths for local and remote repositories
@@ -30,11 +29,19 @@ IF (NOT WEBGPU_TAG)
 ENDIF()
 message(STATUS "Using WebGPU distribution tag: ${WEBGPU_TAG}")
 
-IF (WEBGPU_TAG STREQUAL "dawn")
-  # Pin the dawn backend to a specific commit
-  set(WEBGPU_TAG "1025b977e1927b6d0327e67352f90feb4bcf8274")
+# TODO - look into dawn version check build issue :(
+# ABSL_PROPAGATE_CXX_STD
+# https://github.com/google/dawn/blob/59b4421352ada94c98f0f3d63913c117378d970c/CMakeLists.txt#L246C5-L246C27
+
+if (WEBGPU_TAG STREQUAL "dawn")
+  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -DWEBGPU_BACKEND_DAWN")
+  # actually use specific commit
+  # set(WEBGPU_TAG "1025b977e1927b6d0327e67352f90feb4bcf8274") # prev commit
+  # set(WEBGPU_TAG "acf972b7b909f52e183bdae3971b93bb13d4a29e") # latest commit
+  # add_compile_options(-UABSL_INTERNAL_AT_LEAST_CXX20)
+  # set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -UABSL_INTERNAL_AT_LEAST_CXX20")
   message(STATUS "Using Dawn backend")
-ENDIF()
+endif()
 
 FetchContent_Declare(
   webgpu
@@ -44,11 +51,6 @@ FetchContent_Declare(
 )
 FetchContent_MakeAvailable(webgpu)
 
-if (WEBGPU_TAG STREQUAL "dawn")
-  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -DWEBGPU_BACKEND_DAWN")
-  message(STATUS "Using Dawn backend")
-endif()
-
 option(FASTBUILD "Option to enable fast builds" OFF)
 if(FASTBUILD)
   set(CMAKE_BUILD_TYPE None)  # Avoid default flags of predefined build types

Makefile

@@ -10,7 +10,8 @@ USE_WGPU=-DWEBGPU_TAG=wgpu
 .PHONY: demo tests libgpu debug build check-entr watch-demo watch-tests clean
 
 # Add --trace to see the cmake commands
-FLAGS = -DCMAKE_VERBOSE_MAKEFILE:BOOL=ON -DCMAKE_CXX_COMPILER=$(CXX)
+# absl c++20 check is breaking mac builds
+FLAGS = -DCMAKE_VERBOSE_MAKEFILE:BOOL=ON -DCMAKE_CXX_COMPILER=$(CXX) -DABSL_INTERNAL_AT_LEAST_CXX20=OFF
 
 # TODO(avh): decide whether to use wgpu as default
 FASTBUILD_FLAGS = $(FLAGS) -DFASTBUILD:BOOL=ON
@@ -40,6 +41,9 @@ libgpu: check-dependencies
 debug: check-dependencies
 	$(CMAKE_CMD) $(DEBUG_FLAGS) && make -j$(NUM_JOBS) $(TARGET_ALL)
 
+debug-wgpu: check-dependencies
+	$(CMAKE_CMD) $(DEBUG_FLAGS) $(USE_WGPU) && make -j$(NUM_JOBS) $(TARGET_ALL)
+
 build: check-dependencies
 	$(CMAKE_CMD) $(RELEASE_FLAGS) && make -j$(NUM_JOBS) $(TARGET_ALL)
 
@@ -57,6 +61,7 @@ watch-tests: check-entr check-dependencies
 
 # experimental
 watch-tests-wgpu: check-entr check-dependencies
+	# export RUST_TRACE=1
 	$(CMAKE_CMD) $(FASTBUILD_FLAGS) $(USE_WGPU) && ls ../* ../utils/* | entr -s "rm -f $(TARGET_TESTS) && make -j$(NUM_JOBS) $(TARGET_TESTS) && ./$(TARGET_TESTS)"
 
 watch-demo-local: check-entr check-dependencies

examples/render/run.cpp

@@ -124,12 +124,13 @@ int main(int argc, char **argv) {
     DispatchKernel(ctx, renderKernel);
     Wait(ctx, renderKernel.future);
     ToCPU(ctx, devScreen, screen.data(), sizeof(screen));
-    // Update the time field, write pparams to GPU, and create a new command buffer
+    // Update the time field, write pparams to GPU, and create a new command
+    // buffer
     params.time = getCurrentTimeInMilliseconds() - zeroTime;
     wgpuQueueWriteBuffer(ctx.queue,
                          renderKernel.buffers[renderKernel.numBuffers - 1], 0,
                          static_cast<void *>(&params), sizeof(params));
-    ResetCommandBuffer(ctx.device, shader.workgroupSize, {NCOLS, NROWS, 1},
+    ResetCommandBuffer(ctx.device, /*nthreads*/ {NCOLS, NROWS, 1},
                        renderKernel);
 
     static const char intensity[] = "$@B%8&WM#*oahkbdpqwmZO0QLCJUYXzcvunxrjft/"