Use more commonly-used expression of rounding term

Change-Id: Ic18053845fcedfe12857f2fab51de9d28fa5001b
diff --git a/av1/encoder/arm/highbd_rdopt_neon.c b/av1/encoder/arm/highbd_rdopt_neon.c
index 983a81b..f5a0921 100644
--- a/av1/encoder/arm/highbd_rdopt_neon.c
+++ b/av1/encoder/arm/highbd_rdopt_neon.c
@@ -22,7 +22,7 @@
   int64x2_t ssz_s64 = vdupq_n_s64(0);
 
   const int shift = 2 * (bd - 8);
-  const int rounding = shift > 0 ? 1 << (shift - 1) : 0;
+  const int rounding = (1 << shift) >> 1;
 
   assert(block_size >= 16);
   assert((block_size % 16) == 0);
diff --git a/av1/encoder/rdopt.c b/av1/encoder/rdopt.c
index e315aee..71c7c45 100644
--- a/av1/encoder/rdopt.c
+++ b/av1/encoder/rdopt.c
@@ -665,7 +665,7 @@
   int i;
   int64_t error = 0, sqcoeff = 0;
   int shift = 2 * (bd - 8);
-  int rounding = shift > 0 ? 1 << (shift - 1) : 0;
+  int rounding = (1 << shift) >> 1;
 
   for (i = 0; i < block_size; i++) {
     const int64_t diff = coeff[i] - dqcoeff[i];
diff --git a/av1/encoder/tx_search.c b/av1/encoder/tx_search.c
index 392d73b..74414f0 100644
--- a/av1/encoder/tx_search.c
+++ b/av1/encoder/tx_search.c
@@ -1047,7 +1047,7 @@
   int i;
   int64_t error = 0, sqcoeff = 0;
   int shift = 2 * (bd - 8);
-  int rounding = shift > 0 ? 1 << (shift - 1) : 0;
+  int rounding = (1 << shift) >> 1;
 
   for (i = 0; i < block_size; i++) {
     int64_t weight = qmatrix[scan[i]];
diff --git a/av1/encoder/x86/highbd_block_error_intrin_avx2.c b/av1/encoder/x86/highbd_block_error_intrin_avx2.c
index af4ca08..fec6ea0 100644
--- a/av1/encoder/x86/highbd_block_error_intrin_avx2.c
+++ b/av1/encoder/x86/highbd_block_error_intrin_avx2.c
@@ -23,7 +23,7 @@
   int64_t temp1[8];
   int64_t error = 0, sqcoeff = 0;
   const int shift = 2 * (bps - 8);
-  const int rounding = shift > 0 ? 1 << (shift - 1) : 0;
+  const int rounding = (1 << shift) >> 1;
 
   for (i = 0; i < block_size; i += 16) {
     __m256i mm256_coeff = _mm256_loadu_si256((__m256i *)(coeff + i));
diff --git a/av1/encoder/x86/highbd_block_error_intrin_sse2.c b/av1/encoder/x86/highbd_block_error_intrin_sse2.c
index 502557b..3d843f9 100644
--- a/av1/encoder/x86/highbd_block_error_intrin_sse2.c
+++ b/av1/encoder/x86/highbd_block_error_intrin_sse2.c
@@ -24,7 +24,7 @@
   __m128i max, min, cmp0, cmp1, cmp2, cmp3;
   int64_t error = 0, sqcoeff = 0;
   const int shift = 2 * (bps - 8);
-  const int rounding = shift > 0 ? 1 << (shift - 1) : 0;
+  const int rounding = (1 << shift) >> 1;
 
   for (i = 0; i < block_size; i += 8) {
     // Load the data into xmm registers