addition of ARM NEON intrinsics

openair1/PHY/CODING/nrPolar_tools/nr_polar_decoding_tools.c

@@ -254,6 +254,18 @@ void build_decoder_tree(t_nrPolar_params *pp) {
   			       
 }
 
+#if defined(__arm__) || defined(__aarch64__)
+// translate 1-1 SIMD functions from SSE to NEON
+#define __m128i int16x8_t
+#define __m64 int8x8_t
+#define _mm_abs_epi16(a) vabsq_s16(a)
+#define _mm_min_epi16(a,b) vminq_s16(a,b)
+#define _mm_subs_epi16(a,b) vsubq_s16(a,b)
+#define _mm_abs_pi16(a) vabs_s16(a)
+#define _mm_min_pi16(a,b) vmin_s16(a,b)
+#define _mm_subs_pi16(a,b) vsub_s16(a,b)
+#endif
+
 void applyFtoleft(t_nrPolar_params *pp,decoder_node_t *node) {
   int16_t *alpha_v=node->alpha;
   int16_t *alpha_l=node->left->alpha;
@@ -270,7 +282,6 @@ void applyFtoleft(t_nrPolar_params *pp,decoder_node_t *node) {
  
 
   if (node->left->all_frozen == 0) {
-
 #if defined(__AVX2__)
     int avx2mod = (node->Nv/2)&15;
     if (avx2mod == 0) {
@@ -284,14 +295,7 @@ void applyFtoleft(t_nrPolar_params *pp,decoder_node_t *node) {
 	absa256    =_mm256_abs_epi16(a256);
 	absb256    =_mm256_abs_epi16(b256);
 	minabs256  =_mm256_min_epi16(absa256,absb256);
-	((__m256i*)alpha_l)[i] =_mm256_sign_epi16(minabs256,_mm256_xor_si256(a256,b256));
+	((__m256i*)alpha_l)[i] =_mm256_sign_epi16(minabs256,_mm256_sign_epi16(a256,b256));
-	/*	for (int j=0;j<16;j++) printf("alphal[%d] %d (%d,%d,%d)\n",
-				      (16*i) + j,
-				      alpha_l[(16*i)+j],
-				      ((int16_t*)&minabs256)[j],
-				      alpha_v[(16*i)+j],
-				      alpha_v[(16*i)+j+(node->Nv/2)]);
-	*/
       }
     }
     else if (avx2mod == 8) {
@@ -301,7 +305,7 @@ void applyFtoleft(t_nrPolar_params *pp,decoder_node_t *node) {
       absa128    =_mm_abs_epi16(a128);
       absb128    =_mm_abs_epi16(b128);
       minabs128  =_mm_min_epi16(absa128,absb128);
-      *((__m128i*)alpha_l) =_mm_sign_epi16(minabs128,_mm_xor_si128(a128,b128));
+      *((__m128i*)alpha_l) =_mm_sign_epi16(minabs128,_mm_sign_epi16(a128,b128));
     }
     else if (avx2mod == 4) {
       __m64 a64,b64,absa64,absb64,minabs64;
@@ -310,11 +314,56 @@ void applyFtoleft(t_nrPolar_params *pp,decoder_node_t *node) {
       absa64    =_mm_abs_pi16(a64);
       absb64    =_mm_abs_pi16(b64);
       minabs64  =_mm_min_pi16(absa64,absb64);
-      *((__m64*)alpha_l) =_mm_sign_pi16(minabs64,_mm_xor_si64(a64,b64));
+      *((__m64*)alpha_l) =_mm_sign_pi16(minabs64,_mm_sign_pi16(a64,b64));
     }
     else
+#else
+    int sse4mod = (node->Nv/2)&7;
+    int sse4len = node->Nv/2/8;
+#if defined(__arm__) || defined(__aarch64__)
+    int16x8_t signatimesb,comp1,comp2,negminabs128;
+    int16x8_t zero=vdupq_n_s16(0);
 #endif
-    {
+
+    if (sse4mod == 0) {
+      for (int i=0;i<sse4len;i++) {
+	__m128i a128,b128,absa128,absb128,minabs128;
+	int sse4len = node->Nv/2/8;
+	
+	a128       =*((__m128i*)alpha_v);
+	b128       =((__m128i*)alpha_v)[1];
+	absa128    =_mm_abs_epi16(a128);
+	absb128    =_mm_abs_epi16(b128);
+	minabs128  =_mm_min_epi16(absa128,absb128);
+#if defined(__arm__) || defined(__aarch64__)
+	// unfortunately no direct equivalent to _mm_sign_epi16
+	signatimesb=vxorrq_s16(a128,b128);
+	comp1=vcltq_s16(signatimesb,zero);
+	comp2=vcgeq_s16(signatimesb,zero);
+	negminabs128=vnegq_s16(minabs128);
+	*((__m128i*)alpha_l) =vorrq_s16(vandq_s16(minabs128,comp0),vandq_s16(negminabs128,comp1));
+#else
+	*((__m128i*)alpha_l) =_mm_sign_epi16(minabs128,_mm_sign_epi16(a128,b128));
+#endif
+      }
+    }
+    else if (sse4mod == 4) {
+      __m64 a64,b64,absa64,absb64,minabs64;
+      a64       =*((__m64*)alpha_v);
+      b64       =((__m64*)alpha_v)[1];
+      absa64    =_mm_abs_pi16(a64);
+      absb64    =_mm_abs_pi16(b64);
+      minabs64  =_mm_min_pi16(absa64,absb64);
+#if defined(__arm__) || defined(__aarch64__)
+	AssertFatal(1==0,"Need to do this still for ARM\n");
+#else
+      *((__m64*)alpha_l) =_mm_sign_pi16(minabs64,_mm_sign_epi16(a64,b64));
+#endif
+    }
+
+    else
+#endif
+    { // equvalent scalar code to above, activated only on non x86/ARM architectures
       for (int i=0;i<node->Nv/2;i++) {
 	a=alpha_v[i];
 	b=alpha_v[i+(node->Nv/2)];
@@ -367,9 +416,34 @@ void applyGtoright(t_nrPolar_params *pp,decoder_node_t *node) {
     else if (avx2mod == 8) {
       ((__m128i *)alpha_r)[0] = _mm_subs_epi16(((__m128i *)alpha_v)[1],_mm_sign_epi16(((__m128i *)alpha_v)[0],((__m128i *)betal)[0]));	
     }
+    else if (avx2mod == 4) {
+      ((__m64 *)alpha_r)[0] = _mm_subs_pi16(((__m64 *)alpha_v)[1],_mm_sign_pi16(((__m64 *)alpha_v)[0],((__m64 *)betal)[0]));	
+    }
+    else
+#else
+    int sse4mod = (node->Nv/2)&7;
+
+    if (sse4mod == 0) {
+      int sse4len = node->Nv/2/8;
+      
+      for (int i=0;i<sse4len;i++) {
+#if defined(__arm__) || defined(__aarch64__)
+	((int16x8_t *)alpha_r)[0] = vsubq_s16(((int16x8_t *)alpha_v)[1],vmulq_epi16(((int16x8_t *)alpha_v)[0],((int16x8_t *)betal)[0]));
+#else
+	((__m128i *)alpha_r)[0] = _mm_subs_epi16(((__m128i *)alpha_v)[1],_mm_sign_epi16(((__m128i *)alpha_v)[0],((__m128i *)betal)[0]));
+#endif	
+      }
+    }
+    else if (sse4mod == 4) {
+#if defined(__arm__) || defined(__aarch64__)
+      ((int16x4_t *)alpha_r)[0] = vsub_s16(((int16x4_t *)alpha_v)[1],vmul_epi16(((int16x4_t *)alpha_v)[0],((int16x4_t *)betal)[0]));
+#else
+      ((__m64 *)alpha_r)[0] = _mm_subs_pi16(((__m64 *)alpha_v)[1],_mm_sign_pi16(((__64 *)alpha_v)[0],((__m64 *)betal)[0]));	
+#endif
+    }
     else 
 #endif
-      {
+      {// equvalent scalar code to above, activated only on non x86/ARM architectures
 	for (int i=0;i<node->Nv/2;i++) {
 	  alpha_r[i] = alpha_v[i+(node->Nv/2)] - (betal[i]*alpha_v[i]);
 	}
@@ -385,10 +459,10 @@ void applyGtoright(t_nrPolar_params *pp,decoder_node_t *node) {
 }
 
 
-int16_t minus1[16] = {-1,-1,-1,-1,
+int16_t all1[16] = {1,1,1,1,
-		      -1,-1,-1,-1,
+		    1,1,1,1,
-		      -1,-1,-1,-1,
+		    1,1,1,1,
-		      -1,-1,-1,-1};
+		    1,1,1,1};
 
 void computeBeta(t_nrPolar_params *pp,decoder_node_t *node) {
 
@@ -401,27 +475,37 @@ void computeBeta(t_nrPolar_params *pp,decoder_node_t *node) {
   if (node->left->all_frozen==0) { // if left node is not aggregation of frozen bits
 #if defined(__AVX2__) 
     int avx2mod = (node->Nv/2)&15;
+    register __m256i allones=*((__m256i*)all1);
     if (avx2mod == 0) {
       int avx2len = node->Nv/2/16;
-      
       for (int i=0;i<avx2len;i++) {
-	((__m256i*)betav)[i] = _mm256_sign_epi16(((__m256i*)betar)[i],
+	((__m256i*)betav)[i] = _mm256_or_si256(_mm256_cmpeq_epi16(((__m256i*)betar)[i],
-						  ((__m256i*)betal)[i]);
+								  ((__m256i*)betal)[i]),allones);
-	((__m256i*)betav)[i] = _mm256_sign_epi16(((__m256i*)betav)[i],
-						  ((__m256i*)minus1)[0]);
       }
     }
     else if (avx2mod == 8) {
-      ((__m128i*)betav)[0] = _mm_sign_epi16(((__m128i*)betar)[0],
+      ((__m128i*)betav)[0] = _mm_or_si128(_mm_cmpeq_epi16(((__m128i*)betar)[0],
-					    ((__m128i*)betal)[0]);
+							  ((__m128i*)betal)[0]),*((__m128i*)all1));
-      ((__m128i*)betav)[0] = _mm_sign_epi16(((__m128i*)betav)[0],
-					    ((__m128i*)minus1)[0]);
     }
     else if (avx2mod == 4) {
-      ((__m64*)betav)[0] = _mm_sign_pi16(((__m64*)betar)[0],
+      ((__m64*)betav)[0] = _mm_or_si64(_mm_cmpeq_pi16(((__m64*)betar)[0],
-					 ((__m64*)betal)[0]);
+						      ((__m64*)betal)[0]),*((__m64*)all1));
-      ((__m64*)betav)[0] = _mm_sign_pi16(((__m64*)betav)[0],
+    }
-					 ((__m64*)minus1)[0]);
+    else
+#else
+    int avx2mod = (node->Nv/2)&15;
+
+    if (ssr4mod == 0) {
+      int ssr4len = node->Nv/2/8;
+      register __m128i allones=*((__m128i*)all1);
+      for (int i=0;i<sse4len;i++) {
+      ((__m256i*)betav)[i] = _mm_or_si128(_mm_cmpeq_epi16(((__m128i*)betar)[i],
+							  ((__m128i*)betal)[i]),allones));
+      }
+    }
+    else if (sse4mod == 4) {
+      ((__m64*)betav)[0] = _mm_or_si64(_mm_cmpeq_pi16(((__m64*)betar)[0],
+						      ((__m64*)betal)[0]),*((__m64*)all1));
     }
     else
 #endif