travis: Test with disabled CPU feature detection

Ensure that fallbacks are working correctly.

.travis.yml

@@ -2,7 +2,8 @@ language: cpp
 
 matrix:
   include:
-    - os: linux
+    - env: NAME="Linux Build"
+      os: linux
       dist: trusty
       addons:
         apt:
@@ -13,7 +14,8 @@ matrix:
             - g++-7
       install: ./.travis/build-x86_64-linux/deps.sh
       script: ./.travis/build-x86_64-linux/build.sh
-    - os: linux
+    - env: NAME="Test - Fuzz against Unicorn"
+      os: linux
       dist: trusty
       addons:
         apt:
@@ -24,7 +26,20 @@ matrix:
             - g++-7
       install: ./.travis/test-a64-on-x86_64-linux/deps.sh
       script: ./.travis/test-a64-on-x86_64-linux/build.sh
-    - os: osx
+    - env: NAME="Test - SSE3 only"
+      os: linux
+      dist: trusty
+      addons:
+        apt:
+          sources:
+            - ubuntu-toolchain-r-test
+          packages:
+            - gcc-7
+            - g++-7
+      install: ./.travis/sse3-only-on-x86_64-linux/deps.sh
+      script: ./.travis/sse3-only-on-x86_64-linux/build.sh
+    - env: NAME="macOS Build"
+      os: osx
       sudo: false
       osx_image: xcode9.2
       install: ./.travis/build-x86_64-macos/deps.sh

.travis/sse3-only-on-x86_64-linux/build.sh

@@ -0,0 +1,15 @@
+#!/bin/sh
+
+set -e
+set -x
+
+export CC=gcc-7
+export CXX=g++-7
+export PKG_CONFIG_PATH=$HOME/.local/lib/pkgconfig:$PKG_CONFIG_PATH
+export UNICORNDIR=$(pwd)/externals/unicorn
+
+mkdir build && cd build
+cmake .. -DBoost_INCLUDE_DIRS=${PWD}/../externals/ext-boost -DCMAKE_BUILD_TYPE=Release -DDYNARMIC_TESTS_USE_UNICORN=1 -DDYNARMIC_ENABLE_CPU_FEATURE_DETECTION=0
+make -j4
+
+./tests/dynarmic_tests --durations yes

.travis/sse3-only-on-x86_64-linux/deps.sh

@@ -0,0 +1,16 @@
+#!/bin/sh
+
+set -e
+set -x
+
+# TODO: This isn't ideal.
+cd externals
+git clone https://github.com/MerryMage/ext-boost
+git clone https://github.com/MerryMage/unicorn
+cd unicorn
+UNICORN_ARCHS=aarch64 ./make.sh
+cd ../..
+
+mkdir -p $HOME/.local
+curl -L https://cmake.org/files/v3.8/cmake-3.8.0-Linux-x86_64.tar.gz \
+    | tar -xz -C $HOME/.local --strip-components=1

CMakeLists.txt

@@ -9,6 +9,7 @@ if (CMAKE_CURRENT_SOURCE_DIR STREQUAL CMAKE_SOURCE_DIR)
 endif()
 
 # Dynarmic project options
+option(DYNARMIC_ENABLE_CPU_FEATURE_DETECTION "Turning this off causes dynarmic to assume the host CPU doesn't support anything later than SSE3" ON)
 option(DYNARMIC_USE_LLVM "Support disassembly of jitted x86_64 code using LLVM" OFF)
 option(DYNARMIC_TESTS "Build tests" ${MASTER_PROJECT})
 option(DYNARMIC_TESTS_USE_UNICORN "Enable fuzzing tests against unicorn" OFF)

src/CMakeLists.txt

@@ -167,6 +167,9 @@ target_link_libraries(dynarmic
         xbyak
         $<$<BOOL:DYNARMIC_USE_LLVM>:${llvm_libs}>
 )
+if (DYNARMIC_ENABLE_CPU_FEATURE_DETECTION)
+    target_compile_definitions(dynarmic PRIVATE DYNARMIC_ENABLE_CPU_FEATURE_DETECTION=1)
+endif()
 if (CMAKE_SYSTEM_NAME STREQUAL "Windows")
     target_compile_definitions(dynarmic PRIVATE FMT_USE_WINDOWS_H=0)
 endif()

src/backend_x64/block_of_code.cpp

@@ -235,7 +235,11 @@ void BlockOfCode::EnsurePatchLocationSize(CodePtr begin, size_t size) {
 }
 
 bool BlockOfCode::DoesCpuSupport(Xbyak::util::Cpu::Type type) const {
+#ifdef DYNARMIC_ENABLE_CPU_FEATURE_DETECTION
     return cpu_info.has(type);
+#else
+    return false;
+#endif
 }
 
 } // namespace BackendX64