CMake: Updates

Issue #294: "apple silicon build problem(s?)": If the "--flavor/-f" flag
is not specified on the command line, then complain loudly, print help
and exit. The script used to default to "Unix Makefiles".

Updates:

- Add missing "-DHAVE_LIBPNG" compiler command line define when the PNG
  library is detected/present for screen capture support.

- Add "clang64" to the list of MinGW64 platforms for which the
  .travis/deps.sh script can install build dependencies.

- Add PThread4W_FOUND to the condition that sets async I/O for Win32
  when using vcpkg for build dependencies.

- Add vs2022-x64, vs2019-x64 and vs2017-x64 build environments to
  build 64-bit Windows executables.

- Use simulator AIO only where needed by the simulator (i.e., the
  simulator calls/uses AIO_CHECK_EVENT in sim_instr())

  - Add "USES_AIO" flag to add_simulator() to mark a simulator that
    acutally uses asynchronous I/O.

  - Build "_aio" SIMH core library variants that have AIO turned on,
    link with the "_aio" variant when a simulator sets USES_AIO.

  - Emit a warning message when WITH_ASYNC is False (CMake configuration
    option) to notify the user/developer that some functionality will be
    crippled.

  Affected simulator builds: 3b2 family, PDP-6, PDP-11, VAX family,
  IMLAC and TT2500. The makefile and cmake/generate.py also updated
  to remain in sync with CMake.

  N.B.: Simulators still link with the underlying platform's threading
  library. SEL32 requires pthreads or equivalent threading library,
  independent of AIO.

- cmake/cmake-builder.sh

  - New "--no-aio" flag: Build simulators without async I/O.

  - New "--no-aio-intrinsics" flag: Don't build async I/O using compiler
    compare-exchange, atomic load intrinsics.

- cmake/cmake-builder.ps1

  - New "-noaio" flag: Build simulators without async I/O.

  - New "-noaiointrinsics" flag: Don't build async I/O using compiler
    compare-exchange, atomic load intrinsics.

CMake 3.28.1 INTERFACE_LINK_LIBRARIES behavior change: The file name
must now be an absolute path. Relative paths no longer accepted.
Internally, SIMH enforces this if CMAKE_VERSION >= 3.19, when REAL_PATH
was first implemented.

Author: bscottm

.travis/deps.sh

@@ -45,8 +45,22 @@ install_ucrt64() {
 	mingw-w64-ucrt-x86_64-libpcap
 }
 
+install_clang64() {
+    pacman -S --needed mingw-w64-clang-x86_64-ninja \
+	mingw-w64-clang-x86_64-cmake \
+	mingw-w64-clang-x86_64-extra-cmake-modules \
+        mingw-w64-clang-x86_64-clang \
+	mingw-w64-clang-x86_64-make \
+        mingw-w64-clang-x86_64-pcre \
+	mingw-w64-clang-x86_64-freetype \
+        mingw-w64-clang-x86_64-SDL2 \
+	mingw-w64-clang-x86_64-SDL2_ttf \
+	mingw-w64-clang-x86_64-libpcap
+}
+
+
 case "$1" in
-  osx|linux|mingw64|ucrt64)
+  osx|linux|mingw64|ucrt64|clang64)
     install_"$1"
     ;;
   *)

3B2/CMakeLists.txt

@@ -38,6 +38,7 @@ add_simulator(3b2
     DEFINES
         REV2
     FEATURE_FULL64
+    USES_AIO
     LABEL 3B2
     PKG_FAMILY att3b2_family
     TEST 3b2)
@@ -65,6 +66,7 @@ add_simulator(3b2-700
     DEFINES
         REV3
     FEATURE_FULL64
+    USES_AIO
     LABEL 3B2
     PKG_FAMILY att3b2_family
     TEST 3b2-700)

CMakeLists.txt

@@ -28,6 +28,13 @@ if (CMAKE_VERSION VERSION_LESS "3.21" AND NOT DEFINED SIMH_INSTALLER_WARNING)
     set(SIMH_INSTALLER_WARNING TRUE CACHE BOOL "Installer/CPack warning issued when CMAKE_VERSION < 3.21" FORCE)
 endif ()
 
+## SIMH Version variables:
+set(SIMH_VERSION_MAJOR 4)
+set(SIMH_VERSION_MINOR 1)
+set(SIMH_VERSION_PATCH 0)
+set(SIMH_VERSION "${SIMH_VERSION_MAJOR}.${SIMH_VERSION_MINOR}.${SIMH_VERSION_PATCH}"
+    CACHE PATH "Open-Simh version string.")
+
 # Places to look for CMake modules/includes
 set(SIMH_INCLUDE_PATH_LIST
     ${CMAKE_SOURCE_DIR}/cmake
@@ -73,12 +80,6 @@ if (CMAKE_VERSION VERSION_GREATER_EQUAL 3.15)
     cmake_policy(SET CMP0091 NEW)
 endif()
 
-## SIMH Version variables:
-set(SIMH_VERSION_MAJOR 4)
-set(SIMH_VERSION_MINOR 1)
-set(SIMH_VERSION_PATCH 0)
-set(SIMH_VERSION "${SIMH_VERSION_MAJOR}.${SIMH_VERSION_MINOR}.${SIMH_VERSION_PATCH}")
-
 project(simh VERSION "${SIMH_VERSION}" LANGUAGES C CXX)
 
 include(vcpkg-setup)

PDP10/CMakeLists.txt

@@ -226,6 +226,7 @@ add_simulator(pdp6
     FEATURE_INT64
     FEATURE_VIDEO
     FEATURE_DISPLAY
+    USES_AIO
     LABEL PDP10
     PKG_FAMILY decpdp_family
     TEST pdp6)

PDP11/CMakeLists.txt

@@ -74,6 +74,7 @@ add_simulator(pdp11
         VM_PDP11
     FEATURE_VIDEO
     FEATURE_DISPLAY
+    USES_AIO
     BUILDROMS
     LABEL PDP11
     PKG_FAMILY pdp11_family

README-CMake.md

@@ -1189,13 +1189,15 @@ add_simulator(3b2
       convention `[sim]_test.ini` -- the argument to the `TEST` parameter is the
       `[sim]` portion of the test script's name.
 
-- Option keywords: These determine which of [six (6) simulator core libraries](#simulator-core-libraries) is
+- Option keywords: These determine which of [simulator core libraries](#simulator-core-libraries) is
   linked with the simulator.
 
   - `FEATURE_INT64`: 64-bit integers, 32-bit pointers
   - `FEATURE_FULL64`: 64-bit integers, 64-bit pointers
   - `FEATURE_VIDEO`: Simulator video support.
   - `FEATURE_DISPLAY`: Video display support.
+  - `USES_AIO`: Asynchronous I/O support (primarily useful for simulator
+    network devices.)
 
 - `PKG_FAMILY` option: This option adds the simulator to a package "family" or
   simulator packaging group, e.g., "DEC PDP simulators". The default package
@@ -1213,14 +1215,31 @@ The `CMake` build infrastructure avoids repeatedly compiling the simulator
 libraries that represents the combination of required features: 32/64 bit
 support and video:
 
-| Library          | Video | Integer size | Address size | `add_simulator` flags |
-| :--------------- | :---: | -----------: | -----------: | :-------------------- |
-| simhcore.a       | N     | 32           | 32           |                       |
-| simhi64.a        | N     | 64           | 32           | `FEATURE_INT64`       |
-| simhz64.a        | N     | 64           | 64           | `FEATURE_FULL64`      |
-| simhcore_video.a | Y     | 32           | 32           | `FEATURE_VIDEO`       |
-| simhi64_video.a  | Y     | 64           | 32           | `FEATURE_INT64`, `FEATURE_VIDEO` |
-| simhz64_video.a  | Y     | 64           | 64           | `FEATURE_FULL64`, `FEATURE_VIDEO` |
+| Library           | Video | Integer size | Address size | `add_simulator` flags |
+| :---------------- | :---: | -----------: | -----------: | :-------------------- |
+| simhcore.a        | N     | 32           | 32           |                       |
+| simhi64.a         | N     | 64           | 32           | `FEATURE_INT64`       |
+| simhz64.a         | N     | 64           | 64           | `FEATURE_FULL64`      |
+| simhcore\_video.a | Y     | 32           | 32           | `FEATURE_VIDEO`       |
+| simhi64\_video.a  | Y     | 64           | 32           | `FEATURE_INT64`, `FEATURE_VIDEO` |
+| simhz64\_video.a  | Y     | 64           | 64           | `FEATURE_FULL64`, `FEATURE_VIDEO` |
+
+In addition to these six libraries, there are six asynchronous I/O (AIO)
+variants that are built and linked into a simulator when the `USES_AIO` feature
+flag is present in `add_simulator()`'s arguments:
+
+| Library variant        | Description |
+| :--------------------- | :---------: |
+| simhcore\_aio.a        | simhcore.a with AIO support.        |
+| simhi64\_aio.a         | simhi64.a with AIO support.         |
+| simhz64\_aio.a         | simhz64.a with AIO support.         |
+| simhcore\_video\_aio.a | simhcore\_video.a with AIO support. |
+| simhi64\_video\_aio.a  | simhi64\_video.a with AIO support.  |
+| simhz64\_video\_aio.a  | simhz64\_video.a with AIO support.  |
+
+The `EXCLUDE_FROM_ALL` property is set on each of theses libraries in CMake to
+avoid building the entire matrix. Practically speaking, 10 out of the 12 total
+libraries actually build for the entire simulator suite.
 
 Internally, these core libraries are [`CMake` interface libraries][cmake_interface_library] -- when they
 are added to a simulator's executable via `target_link_libraries`, the simulator
@@ -1265,6 +1284,10 @@ add_simulator(simulator_name
     ## in conjunction with FEATURE_VIDEO
     FEATURE_DISPLAY
 
+    ## Simulator uses asynchronous I/O, i.e., calls AIO_CHECK_EVENT
+    ## in its sim_instr() instruction simulation loop:
+    USES_AIO
+
     ## Packaging "family" (group) to which the simulator belongs,
     ## for packagers that support grouping (Windows: NSIS .exe,
     ## WIX .msi; macOS)

VAX/CMakeLists.txt

@@ -140,6 +140,7 @@ add_simulator(infoserver100
         VAX_411
     FEATURE_FULL64
     FEATURE_VIDEO
+    USES_AIO
     BUILDROMS
     LABEL VAX
     PKG_FAMILY vax_family
@@ -169,6 +170,7 @@ add_simulator(infoserver1000
         VM_VAX
         IS_1000
     FEATURE_FULL64
+    USES_AIO
     BUILDROMS
     LABEL VAX
     PKG_FAMILY vax_family
@@ -186,6 +188,7 @@ add_simulator(infoserver150vxt
         VAX_412
     FEATURE_FULL64
     FEATURE_VIDEO
+    USES_AIO
     BUILDROMS
     LABEL VAX
     PKG_FAMILY vax_family
@@ -230,6 +233,7 @@ add_simulator(microvax1
         VAX_610
     FEATURE_FULL64
     FEATURE_VIDEO
+    USES_AIO
     BUILDROMS
     LABEL VAX
     PKG_FAMILY vax_family
@@ -246,6 +250,7 @@ add_simulator(microvax2
         VAX_630
     FEATURE_FULL64
     FEATURE_VIDEO
+    USES_AIO
     BUILDROMS
     LABEL VAX
     PKG_FAMILY vax_family
@@ -283,6 +288,7 @@ add_simulator(microvax2000
         VAX_410
     FEATURE_FULL64
     FEATURE_VIDEO
+    USES_AIO
     BUILDROMS
     LABEL VAX
     PKG_FAMILY vax_family
@@ -300,6 +306,7 @@ add_simulator(microvax3100
         VAX_41A
     FEATURE_FULL64
     FEATURE_VIDEO
+    USES_AIO
     BUILDROMS
     LABEL VAX
     PKG_FAMILY vax_family
@@ -317,6 +324,7 @@ add_simulator(microvax3100e
         VAX_41D
     FEATURE_FULL64
     FEATURE_VIDEO
+    USES_AIO
     BUILDROMS
     LABEL VAX
     PKG_FAMILY vax_family
@@ -332,6 +340,7 @@ add_simulator(microvax3100m80
         VAX_440
         VAX_47
     FEATURE_FULL64
+    USES_AIO
     BUILDROMS
     LABEL VAX
     PKG_FAMILY vax_family
@@ -362,6 +371,7 @@ add_simulator(vax
         VM_VAX
     FEATURE_FULL64
     FEATURE_VIDEO
+    USES_AIO
     BUILDROMS
     LABEL VAX
     PKG_FAMILY vax_family
@@ -435,6 +445,7 @@ add_simulator(vax730
         VM_VAX
         VAX_730
     FEATURE_FULL64
+    USES_AIO
     BUILDROMS
     LABEL VAX
     PKG_FAMILY vax_family
@@ -485,6 +496,7 @@ add_simulator(vax750
         VM_VAX
         VAX_750
     FEATURE_FULL64
+    USES_AIO
     BUILDROMS
     LABEL VAX
     PKG_FAMILY vax_family
@@ -536,6 +548,7 @@ add_simulator(vax780
         VM_VAX
         VAX_780
     FEATURE_FULL64
+    USES_AIO
     BUILDROMS
     LABEL VAX
     PKG_FAMILY vax_family
@@ -584,6 +597,7 @@ add_simulator(vax8200
         VM_VAX
         VAX_820
     FEATURE_FULL64
+    USES_AIO
     BUILDROMS
     LABEL VAX
     PKG_FAMILY vax_family
@@ -633,6 +647,7 @@ add_simulator(vax8600
         VM_VAX
         VAX_860
     FEATURE_FULL64
+    USES_AIO
     BUILDROMS
     LABEL VAX
     PKG_FAMILY vax_family
@@ -650,6 +665,7 @@ add_simulator(vaxstation3100m30
         VAX_42A
     FEATURE_FULL64
     FEATURE_VIDEO
+    USES_AIO
     BUILDROMS
     LABEL VAX
     PKG_FAMILY vax_family
@@ -667,6 +683,7 @@ add_simulator(vaxstation3100m38
         VAX_42B
     FEATURE_FULL64
     FEATURE_VIDEO
+    USES_AIO
     BUILDROMS
     LABEL VAX
     PKG_FAMILY vax_family
@@ -702,6 +719,7 @@ add_simulator(vaxstation3100m76
         VAX_43
     FEATURE_FULL64
     FEATURE_VIDEO
+    USES_AIO
     BUILDROMS
     LABEL VAX
     PKG_FAMILY vax_family
@@ -717,6 +735,7 @@ add_simulator(vaxstation4000m60
         VAX_440
         VAX_46
     FEATURE_FULL64
+    USES_AIO
     BUILDROMS
     LABEL VAX
     PKG_FAMILY vax_family
@@ -732,6 +751,7 @@ add_simulator(vaxstation4000vlc
         VAX_440
         VAX_48
     FEATURE_FULL64
+    USES_AIO
     BUILDROMS
     LABEL VAX
     PKG_FAMILY vax_family