# Backport of: https://gitlab.com/libeigen/eigen/-/commit/4d05765345e7e4a984d600039f797e2fede924f3

--- Eigen/src/Core/util/ConfigureVectorization.h.orig	2021-08-19 04:41:58.000000000 +0800
+++ Eigen/src/Core/util/ConfigureVectorization.h	2023-01-18 02:25:19.000000000 +0800
@@ -363,10 +363,10 @@
       #endif
     } // end extern "C"
 
-  #elif defined __VSX__
+  #elif defined(__VSX__) && !defined(__APPLE__)
 
     #define EIGEN_VECTORIZE
-    #define EIGEN_VECTORIZE_VSX
+    #define EIGEN_VECTORIZE_VSX 1
     #include <altivec.h>
     // We need to #undef all these ugly tokens defined in <altivec.h>
     // => use __vector instead of vector

--- Eigen/src/Core/util/Macros.h.orig	2021-08-19 04:41:58.000000000 +0800
+++ Eigen/src/Core/util/Macros.h	2023-01-18 02:21:23.000000000 +0800
@@ -329,7 +329,7 @@
 #endif
 
 /// \internal EIGEN_ARCH_PPC set to 1 if the architecture is PowerPC
-#if defined(__powerpc__) || defined(__ppc__) || defined(_M_PPC)
+#if defined(__powerpc__) || defined(__ppc__) || defined(_M_PPC) || defined(__POWERPC__)
   #define EIGEN_ARCH_PPC 1
 #else
   #define EIGEN_ARCH_PPC 0
@@ -1127,8 +1127,13 @@
       // This seems to be broken on clang.  Packet4f is loaded into a single
       //   register rather than a vector, zeroing out some entries.  Integer
       //   types also generate a compile error.
-      // General, Altivec, VSX.
-      #define EIGEN_OPTIMIZATION_BARRIER(X)  __asm__  ("" : "+r,v,wa" (X));
+      #if EIGEN_OS_MAC
+        // General, Altivec for Apple (VSX were added in ISA v2.06):
+        #define EIGEN_OPTIMIZATION_BARRIER(X)  __asm__  ("" : "+r,v" (X));
+      #else
+        // General, Altivec, VSX otherwise:
+        #define EIGEN_OPTIMIZATION_BARRIER(X)  __asm__  ("" : "+r,v,wa" (X));
+      #endif
     #elif EIGEN_ARCH_ARM_OR_ARM64
       // General, NEON.
       #define EIGEN_OPTIMIZATION_BARRIER(X)  __asm__  ("" : "+g,w" (X));

--- Eigen/src/Core/arch/AltiVec/Complex.h.orig	2021-08-19 04:41:58.000000000 +0800
+++ Eigen/src/Core/arch/AltiVec/Complex.h	2023-01-18 02:27:46.000000000 +0800
@@ -16,7 +16,7 @@
 namespace internal {
 
 static Packet4ui  p4ui_CONJ_XOR = vec_mergeh((Packet4ui)p4i_ZERO, (Packet4ui)p4f_MZERO);//{ 0x00000000, 0x80000000, 0x00000000, 0x80000000 };
-#ifdef __VSX__
+#ifdef EIGEN_VECTORIZE_VSX
 #if defined(_BIG_ENDIAN)
 static Packet2ul  p2ul_CONJ_XOR1 = (Packet2ul) vec_sld((Packet4ui) p2d_MZERO, (Packet4ui) p2l_ZERO, 8);//{ 0x8000000000000000, 0x0000000000000000 };
 static Packet2ul  p2ul_CONJ_XOR2 = (Packet2ul) vec_sld((Packet4ui) p2l_ZERO,  (Packet4ui) p2d_MZERO, 8);//{ 0x8000000000000000, 0x0000000000000000 };
@@ -100,7 +100,7 @@
     HasAbs2   = 0,
     HasMin    = 0,
     HasMax    = 0,
-#ifdef __VSX__
+#ifdef EIGEN_VECTORIZE_VSX
     HasBlend  = 1,
 #endif
     HasSetLinear = 0
@@ -130,7 +130,7 @@
 EIGEN_STRONG_INLINE Packet2cf pload2(const std::complex<float>* from0, const std::complex<float>* from1)
 {
   Packet4f res0, res1;
-#ifdef __VSX__
+#ifdef EIGEN_VECTORIZE_VSX
   __asm__ ("lxsdx %x0,%y1" : "=wa" (res0) : "Z" (*from0));
   __asm__ ("lxsdx %x0,%y1" : "=wa" (res1) : "Z" (*from1));
 #ifdef _BIG_ENDIAN
@@ -233,7 +233,7 @@
   return Packet2cf(vec_and(eq, vec_perm(eq, eq, p16uc_COMPLEX32_REV)));
 }
 
-#ifdef __VSX__
+#ifdef EIGEN_VECTORIZE_VSX
 template<> EIGEN_STRONG_INLINE Packet2cf pblend(const Selector<2>& ifPacket, const Packet2cf& thenPacket, const Packet2cf& elsePacket) {
   Packet2cf result;
   result.v = reinterpret_cast<Packet4f>(pblend<Packet2d>(ifPacket, reinterpret_cast<Packet2d>(thenPacket.v), reinterpret_cast<Packet2d>(elsePacket.v)));
@@ -247,7 +247,7 @@
 }
 
 //---------- double ----------
-#ifdef __VSX__
+#ifdef EIGEN_VECTORIZE_VSX
 struct Packet1cd
 {
   EIGEN_STRONG_INLINE Packet1cd() {}

--- Eigen/src/Core/arch/AltiVec/MathFunctions.h.orig	2021-08-19 04:41:58.000000000 +0800
+++ Eigen/src/Core/arch/AltiVec/MathFunctions.h	2023-01-18 02:28:17.000000000 +0800
@@ -48,7 +48,7 @@
 }
 #endif
 
-#ifdef __VSX__
+#ifdef EIGEN_VECTORIZE_VSX
 #ifndef EIGEN_COMP_CLANG
 template<> EIGEN_DEFINE_FUNCTION_ALLOWING_MULTIPLE_DEFINITIONS EIGEN_UNUSED
 Packet2d prsqrt<Packet2d>(const Packet2d& x)

--- Eigen/src/Core/arch/AltiVec/PacketMath.h.orig	2021-08-19 04:41:58.000000000 +0800
+++ Eigen/src/Core/arch/AltiVec/PacketMath.h	2023-01-18 02:32:28.000000000 +0800
@@ -84,7 +84,7 @@
 static _EIGEN_DECLARE_CONST_FAST_Packet8us(ONE,1); //{ 1, 1, 1, 1, 1, 1, 1, 1}
 static _EIGEN_DECLARE_CONST_FAST_Packet16uc(ONE,1);
 static Packet4f p4f_MZERO = (Packet4f) vec_sl((Packet4ui)p4i_MINUS1, (Packet4ui)p4i_MINUS1); //{ 0x80000000, 0x80000000, 0x80000000, 0x80000000}
-#ifndef __VSX__
+#ifndef EIGEN_VECTORIZE_VSX
 static Packet4f p4f_ONE = vec_ctf(p4i_ONE, 0); //{ 1.0, 1.0, 1.0, 1.0}
 #endif
 
@@ -114,7 +114,7 @@
 // Define global static constants:
 #ifdef _BIG_ENDIAN
 static Packet16uc p16uc_FORWARD = vec_lvsl(0, (float*)0);
-#ifdef __VSX__
+#ifdef EIGEN_VECTORIZE_VSX
 static Packet16uc p16uc_REVERSE64 = { 8,9,10,11, 12,13,14,15, 0,1,2,3, 4,5,6,7 };
 #endif
 static Packet16uc p16uc_PSET32_WODD   = vec_sld((Packet16uc) vec_splat((Packet4ui)p16uc_FORWARD, 0), (Packet16uc) vec_splat((Packet4ui)p16uc_FORWARD, 2), 8);//{ 0,1,2,3, 0,1,2,3, 8,9,10,11, 8,9,10,11 };
@@ -168,7 +168,7 @@
     HasCos = EIGEN_FAST_MATH,
     HasLog = 1,
     HasExp = 1,
-#ifdef __VSX__
+#ifdef EIGEN_VECTORIZE_VSX
     HasSqrt = 1,
 #if !EIGEN_COMP_CLANG
     HasRsqrt = 1,
@@ -210,7 +210,7 @@
     HasCos = EIGEN_FAST_MATH,
     HasLog = 1,
     HasExp = 1,
-#ifdef __VSX__
+#ifdef EIGEN_VECTORIZE_VSX
     HasSqrt = 1,
 #if !EIGEN_COMP_CLANG
     HasRsqrt = 1,
@@ -432,7 +432,7 @@
   // ignoring these warnings for now.
   EIGEN_UNUSED_VARIABLE(from);
   EIGEN_DEBUG_ALIGNED_LOAD
-#ifdef __VSX__
+#ifdef EIGEN_VECTORIZE_VSX
   return vec_xl(0, const_cast<__UNPACK_TYPE__(Packet)*>(from));
 #else
   return vec_ld(0, from);
@@ -481,7 +481,7 @@
   // ignoring these warnings for now.
   EIGEN_UNUSED_VARIABLE(to);
   EIGEN_DEBUG_ALIGNED_STORE
-#ifdef __VSX__
+#ifdef EIGEN_VECTORIZE_VSX
   vec_xst(from, 0, to);
 #else
   vec_st(from, 0, to);
@@ -802,7 +802,7 @@
 
 template<> EIGEN_STRONG_INLINE Packet4f pdiv<Packet4f>(const Packet4f& a, const Packet4f& b)
 {
-#ifndef __VSX__  // VSX actually provides a div instruction
+#ifndef EIGEN_VECTORIZE_VSX  // VSX actually provides a div instruction
   Packet4f t, y_0, y_1;
 
   // Altivec does not offer a divide instruction, we have to do a reciprocal approximation
@@ -831,7 +831,7 @@
 
 template<> EIGEN_STRONG_INLINE Packet4f pmin<Packet4f>(const Packet4f& a, const Packet4f& b)
 {
-  #ifdef __VSX__
+  #ifdef EIGEN_VECTORIZE_VSX
   // NOTE: about 10% slower than vec_min, but consistent with std::min and SSE regarding NaN
   Packet4f ret;
   __asm__ ("xvcmpgesp %x0,%x1,%x2\n\txxsel %x0,%x1,%x2,%x0" : "=&wa" (ret) : "wa" (a), "wa" (b));
@@ -849,7 +849,7 @@
 
 template<> EIGEN_STRONG_INLINE Packet4f pmax<Packet4f>(const Packet4f& a, const Packet4f& b)
 {
-  #ifdef __VSX__
+  #ifdef EIGEN_VECTORIZE_VSX
   // NOTE: about 10% slower than vec_max, but consistent with std::max and SSE regarding NaN
   Packet4f ret;
   __asm__ ("xvcmpgtsp %x0,%x2,%x1\n\txxsel %x0,%x1,%x2,%x0" : "=&wa" (ret) : "wa" (a), "wa" (b));
@@ -923,7 +923,7 @@
     Packet4f t = vec_add(reinterpret_cast<Packet4f>(vec_or(vec_and(reinterpret_cast<Packet4ui>(a), p4ui_SIGN), p4ui_PREV0DOT5)), a);
     Packet4f res;
 
-#ifdef __VSX__
+#ifdef EIGEN_VECTORIZE_VSX
     __asm__("xvrspiz %x0, %x1\n\t"
         : "=&wa" (res)
         : "wa" (t));
@@ -2252,7 +2252,7 @@
 
 
 //---------- double ----------
-#ifdef __VSX__
+#ifdef EIGEN_VECTORIZE_VSX
 typedef __vector double              Packet2d;
 typedef __vector unsigned long long  Packet2ul;
 typedef __vector long long           Packet2l;