Add A32 support in CI

Add A32 support in CI.

Choose Cortex-A32 as test target because it only supports
AArch32. Moreover, Cortex-A32 has Armv8-A Cryptographic Extension,
which is an ideal target for testing Cryptographic Extension conversions.

.github/workflows/github_actions.yml

@@ -55,7 +55,12 @@ jobs:
     runs-on: ubuntu-20.04
     strategy:
       matrix:
-        arch_with_features: [{arch: armv7, feature: none}, {arch: aarch64, feature: none}, {arch: aarch64, feature: crypto+crc}]
+        arch_with_features: [
+          {arch: armv7, feature: none, arch_cflags: none},
+          {arch: aarch64, feature: none, arch_cflags: none},
+          {arch: aarch64, feature: crypto+crc, arch_cflags: none},
+          {arch: armv7, feature: none, arch_cflags: '-mcpu=cortex-a32 -mfpu=neon-fp-armv8'}
+        ]
         cxx_compiler: [g++-10, clang++-11]
     steps:
       - name: checkout code
@@ -69,6 +74,7 @@ jobs:
           distro: ubuntu20.04
           env: |
             CXX: ${{ matrix.cxx_compiler }}
+            ARCH_CFLAGS: ${{ matrix.arch_with_features.arch_cflags }}
           install: |
             apt-get update -q -y
             apt-get install -q -y "${{ matrix.cxx_compiler }}" make

Makefile

@@ -29,14 +29,24 @@ EXEC_WRAPPER = qemu-$(processor)
 endif
 
 # Follow platform-specific configurations
-ifeq ($(processor),$(filter $(processor),aarch64 arm64))
-    ARCH_CFLAGS = -march=armv8-a+fp+simd
-else ifeq ($(processor),$(filter $(processor),i386 x86_64))
-    ARCH_CFLAGS = -maes -mpclmul -mssse3 -msse4.2
-else ifeq ($(processor),$(filter $(processor),arm armv7 armv7l))
-    ARCH_CFLAGS = -mfpu=neon
-else
-    $(error Unsupported architecture)
+ARCH_CFLAGS ?=
+ARCH_CFLAGS_IS_SET =
+ifeq ($(ARCH_CFLAGS),)
+    ARCH_CFLAGS_IS_SET = true
+endif
+ifeq ($(ARCH_CFLAGS),none)
+    ARCH_CFLAGS_IS_SET = true
+endif
+ifdef ARCH_CFLAGS_IS_SET
+    ifeq ($(processor),$(filter $(processor),aarch64 arm64))
+        override ARCH_CFLAGS := -march=armv8-a+fp+simd
+    else ifeq ($(processor),$(filter $(processor),i386 x86_64))
+        override ARCH_CFLAGS := -maes -mpclmul -mssse3 -msse4.2
+    else ifeq ($(processor),$(filter $(processor),arm armv7 armv7l))
+        override ARCH_CFLAGS := -mfpu=neon
+    else
+        $(error Unsupported architecture)
+    endif
 endif
 
 FEATURE ?=

README.md

@@ -119,14 +119,25 @@ $ make FEATURE=crypto+crc check
 
 You can specify GNU toolchain for cross compilation as well.
 [QEMU](https://www.qemu.org/) should be installed in advance.
+
+For ARMv8-A running in 64-bit mode type:
 ```shell
 $ make CROSS_COMPILE=aarch64-linux-gnu- check # ARMv8-A
 ```
-or
+
+For ARMv7-A type:
 ```shell
 $ make CROSS_COMPILE=arm-linux-gnueabihf- check # ARMv7-A
 ```
 
+For ARMv8-A running in 32-bit mode (A32 instruction set), type:
+``` shell
+$ make \
+  CROSS_COMPILE=arm-linux-gnueabihf- \
+  ARCH_CFLAGS="-mcpu=cortex-a32 -mfpu=neon-fp-armv8" \
+  check 
+```
+
 Check the details via [Test Suite for SSE2NEON](tests/README.md).
 
 ## Adoptions