From dbba1328bf01e94f367dd37db448ed377fa677a2 Mon Sep 17 00:00:00 2001
From: Catherine <whitequark@whitequark.org>
Date: Thu, 16 Jan 2025 21:09:33 +0000
Subject: [PATCH] Allow splitting nextpnr-himbaechel per microarchitecture.

This is added primarily for YoWASP.
---
 CMakeLists.txt            | 17 +++++++++---
 README.md                 | 12 +++++++++
 himbaechel/CMakeLists.txt | 56 +++++++++++++++++++++++++++++----------
 3 files changed, 68 insertions(+), 17 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index ed686846..9e621335 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -241,7 +241,18 @@ add_subdirectory(rust)
 add_subdirectory(tests/gui)
 
 function(add_nextpnr_architecture target)
-    cmake_parse_arguments(arg "" "MAIN_SOURCE" "CORE_SOURCES;TEST_SOURCES" ${ARGN})
+    cmake_parse_arguments(arg "" "MAIN_SOURCE" "CORE_SOURCES;TEST_SOURCES;CURRENT_SOURCE_DIR;CURRENT_BINARY_DIR" ${ARGN})
+
+    if (NOT arg_CURRENT_SOURCE_DIR)
+        set(arg_CURRENT_SOURCE_DIR ${CMAKE_CURRENT_SOURCE_DIR})
+    endif()
+    if (NOT arg_CURRENT_BINARY_DIR)
+        set(arg_CURRENT_BINARY_DIR ${CMAKE_CURRENT_BINARY_DIR})
+    endif()
+
+    set(arg_MAIN_SOURCE "${arg_CURRENT_SOURCE_DIR}/${arg_MAIN_SOURCE}")
+    list(TRANSFORM arg_CORE_SOURCES PREPEND ${arg_CURRENT_SOURCE_DIR}/)
+    list(TRANSFORM arg_TEST_SOURCES PREPEND ${arg_CURRENT_SOURCE_DIR}/)
 
     # Defs library: used by everything
     #
@@ -251,7 +262,7 @@ function(add_nextpnr_architecture target)
 
     target_include_directories(nextpnr-${target}-defs INTERFACE
         ${CMAKE_SOURCE_DIR}/common/kernel
-        ${CMAKE_CURRENT_SOURCE_DIR}
+        ${arg_CURRENT_SOURCE_DIR}
     )
 
     string(TOUPPER ${family} family_upper)
@@ -290,7 +301,7 @@ function(add_nextpnr_architecture target)
     endif()
 
     if (BUILD_GUI)
-        add_subdirectory(${CMAKE_SOURCE_DIR}/gui ${CMAKE_CURRENT_BINARY_DIR}/gui)
+        add_subdirectory(${CMAKE_SOURCE_DIR}/gui ${arg_CURRENT_BINARY_DIR}/gui)
 
         # Upsettingly, there is a cyclic dependency between `common/kernel` and `gui`, so these
         # two libraries have to be added separately to all executable targets.
diff --git a/README.md b/README.md
index 9685f968..34c2deaa 100644
--- a/README.md
+++ b/README.md
@@ -181,6 +181,18 @@ sudo make install
 
 To build every available stable architecture, use `-DARCH=all`. To include experimental arches (currently nexus), use `-DARCH=all+alpha`.
 
+### Per-microarchitecture Himbächel
+
+To build a single nextpnr-himbachel executable for each of the supported microarchitectures, use `-DHIMBAECHEL_SPLIT`.
+
+```
+cmake . -DARCH="himbaechel" -DHIMBAECHEL_UARCH="gowin;ng-ultra"
+make -j$(nproc)
+sudo make install
+```
+
+In such a build, instead of a single `nextpnr-himbaechel` binary, two binaries `nextpnr-himbaechel-gowin` and `nextpnr-himbaechel-ng-ultra` are built. Although they are installed together, each microarchitecture is completely independent of the other, and only needs its corresponding `.../share/himbaechel/<microarchitecture>/` chip database directory to run. Split build reduces the size of individual distributed artifacts (although the total size increases), and allows co-installation of artifacts of different versions.
+
 Cross-compilation
 -----------------
 
diff --git a/himbaechel/CMakeLists.txt b/himbaechel/CMakeLists.txt
index e71468df..1fc37b98 100644
--- a/himbaechel/CMakeLists.txt
+++ b/himbaechel/CMakeLists.txt
@@ -1,4 +1,6 @@
-set(SOURCES
+option(HIMBAECHEL_SPLIT "Whether to build one executable per Himbächel microarchitecture" OFF)
+
+set(HIMBAECHEL_SOURCES
     arch.cc
     archdefs.h
     arch.h
@@ -13,24 +15,50 @@ set(SOURCES
     himbaechel_helpers.h
 )
 
-add_nextpnr_architecture(${family}
-    CORE_SOURCES ${SOURCES}
-    MAIN_SOURCE  main.cc
-)
+if (HIMBAECHEL_SPLIT)
 
-function(add_nextpnr_himbaechel_microarchitecture microtarget)
-    cmake_parse_arguments(arg "" "" "CORE_SOURCES;TEST_SOURCES" ${ARGN})
+    function(add_nextpnr_himbaechel_microarchitecture microtarget)
+        cmake_parse_arguments(arg "" "" "CORE_SOURCES;TEST_SOURCES" ${ARGN})
 
-    target_sources(nextpnr-himbaechel-core INTERFACE ${arg_CORE_SOURCES})
+        list(TRANSFORM arg_CORE_SOURCES PREPEND ${CMAKE_CURRENT_SOURCE_DIR}/)
+        list(TRANSFORM arg_TEST_SOURCES PREPEND ${CMAKE_CURRENT_SOURCE_DIR}/)
 
-    add_library(nextpnr-himbaechel-${microtarget}-chipdb INTERFACE)
+        add_nextpnr_architecture(himbaechel-${microtarget}
+            CORE_SOURCES ${HIMBAECHEL_SOURCES}
+            MAIN_SOURCE  main.cc
+            CURRENT_SOURCE_DIR ${CMAKE_SOURCE_DIR}/himbaechel
+            CURRENT_BINARY_DIR ${CMAKE_CURRENT_BINARY_DIR}
+        )
 
-    target_link_libraries(nextpnr-himbaechel-core INTERFACE nextpnr-himbaechel-${microtarget}-chipdb)
+        target_sources(nextpnr-himbaechel-${microtarget}-core INTERFACE ${arg_CORE_SOURCES})
 
-    if (BUILD_TESTS)
-        target_sources(nextpnr-himbaechel-test PRIVATE ${arg_TEST_SOURCES})
-    endif()
-endfunction()
+        if (BUILD_TESTS)
+            target_sources(nextpnr-himbaechel-${microtarget}-test PRIVATE ${arg_TEST_SOURCES})
+        endif()
+    endfunction()
+
+else()
+
+    add_nextpnr_architecture(himbaechel
+        CORE_SOURCES ${HIMBAECHEL_SOURCES}
+        MAIN_SOURCE  main.cc
+    )
+
+    function(add_nextpnr_himbaechel_microarchitecture microtarget)
+        cmake_parse_arguments(arg "" "" "CORE_SOURCES;TEST_SOURCES" ${ARGN})
+
+        target_sources(nextpnr-himbaechel-core INTERFACE ${arg_CORE_SOURCES})
+
+        add_library(nextpnr-himbaechel-${microtarget}-chipdb INTERFACE)
+
+        target_link_libraries(nextpnr-himbaechel-core INTERFACE nextpnr-himbaechel-${microtarget}-chipdb)
+
+        if (BUILD_TESTS)
+            target_sources(nextpnr-himbaechel-test PRIVATE ${arg_TEST_SOURCES})
+        endif()
+    endfunction()
+
+endif()
 
 set(HIMBAECHEL_UARCHES example gowin xilinx ng-ultra)