Make Altivec vector wraps friendly to downgrades

The way the existing ppc_simd.h is written makes it hard to to switch between the old Altivec loads and stores and the new POWER7 loads and stores. This checkin rewrites the wrappers to use _ALTIVEC_, _ARCH_PWR7 and _ARCH_PWR8. The wrappers in this file now honor -maltivec, -mcpu-power7 and -mcpu=power8. It allows users to compile a source file, like chacha_simd.cpp, with a lower ISA and things just work for them.

1 files changed, 12 insertions, 7 deletions

diff --git a/chacha.cpp b/chacha.cpp
index 333a58a6..a89fa016 100644
--- a/chacha.cpp
+++ b/chacha.cpp
@@ -24,7 +24,7 @@ extern void ChaCha_OperateKeystream_SSE2(const word32 *state, const byte* input,
 extern void ChaCha_OperateKeystream_AVX2(const word32 *state, const byte* input, byte *output, unsigned int rounds);

 #endif

 

-#if (CRYPTOPP_POWER7_AVAILABLE)

+#if (CRYPTOPP_ALTIVEC_AVAILABLE)

 extern void ChaCha_OperateKeystream_POWER7(const word32 *state, const byte* input, byte *output, unsigned int rounds);

 #endif

 

@@ -86,6 +86,11 @@ std::string ChaCha_Policy::AlgorithmProvider() const
         return "Power7";

     else

 #endif

+#if (CRYPTOPP_ALTIVEC_AVAILABLE)

+    if (HasAltivec())

+        return "Altivec";

+    else

+#endif

     return "C++";

 }

 

@@ -139,8 +144,8 @@ unsigned int ChaCha_Policy::GetAlignment() const
         return 16;

     else

 #endif

-#if (CRYPTOPP_POWER7_AVAILABLE)

-    if (HasPower7())

+#if (CRYPTOPP_ALTIVEC_AVAILABLE)

+    if (HasAltivec())

         return 16;

     else

 #endif

@@ -164,8 +169,8 @@ unsigned int ChaCha_Policy::GetOptimalBlockSize() const
         return 4*BYTES_PER_ITERATION;

     else

 #endif

-#if (CRYPTOPP_POWER7_AVAILABLE)

-    if (HasPower7())

+#if (CRYPTOPP_ALTIVEC_AVAILABLE)

+    if (HasAltivec())

         return 4*BYTES_PER_ITERATION;

     else

 #endif

@@ -245,8 +250,8 @@ void ChaCha_Policy::OperateKeystream(KeystreamOperation operation,
         }

 #endif

 

-#if (CRYPTOPP_POWER7_AVAILABLE)

-        if (HasPower7())

+#if (CRYPTOPP_ALTIVEC_AVAILABLE)

+        if (HasAltivec())

         {

             while (iterationCount >= 4 && MultiBlockSafe(4))

             {