Audio: DRC: Optimize HiFi4 drc_update_detector_average()

Use 64 bit SIMD for load/store and maximum absolute
values search. This saves about 0.1 MCPS in MTL simulation
in sof-testbench4.

Signed-off-by: Seppo Ingalsuo <[email protected]>

src/audio/drc/drc_hifi4.c

@@ -143,23 +143,29 @@ void drc_update_detector_average(struct drc_state *state,
 		for (ch = 0; ch < nch; ch++) {
 			abs_input_array_p = abs_input_array;
 			sample16_p = (ae_int16 *)state->pre_delay_buffers[ch] + div_start;
-			for (i = 0; i < DRC_DIVISION_FRAMES; i++) {
-				AE_L16_XP(sample16, sample16_p, nbyte);
+			for (i = 0; i < DRC_DIVISION_FRAMES / 4; i++) {
+				AE_L16X4_XP(sample16, sample16_p, sizeof(ae_int16x4));
+
+				sample32 = AE_CVT32X2F16_32(sample16);
+				temp = AE_L32X2_I(abs_input_array_p, 0);
+				sample32 = AE_MAXABS32S(sample32, temp);
+				AE_S32X2_IP(sample32, abs_input_array_p, sizeof(ae_int32x2));
+
 				sample32 = AE_CVT32X2F16_10(sample16);
-				temp = AE_L32_I(abs_input_array_p, 0);
+				temp = AE_L32X2_I(abs_input_array_p, 0);
 				sample32 = AE_MAXABS32S(sample32, temp);
-				AE_S32_L_XP(sample32, abs_input_array_p, 4);
+				AE_S32X2_IP(sample32, abs_input_array_p, sizeof(ae_int32x2));
 			}
 		}
 	} else { /* 4 bytes per sample */
 		for (ch = 0; ch < nch; ch++) {
 			abs_input_array_p = abs_input_array;
 			sample32_p = (ae_int32 *)state->pre_delay_buffers[ch] + div_start;
-			for (i = 0; i < DRC_DIVISION_FRAMES; i++) {
-				AE_L32_XP(sample32, sample32_p, nbyte);
-				temp = AE_L32_I(abs_input_array_p, 0);
+			for (i = 0; i < DRC_DIVISION_FRAMES / 2; i++) {
+				AE_L32X2_IP(sample32, sample32_p, sizeof(ae_int32x2));
+				temp = AE_L32X2_I(abs_input_array_p, 0);
 				sample32 = AE_MAXABS32S(sample32, temp);
-				AE_S32_L_XP(sample32, abs_input_array_p, nbyte);
+				AE_S32X2_IP(sample32, abs_input_array_p, sizeof(ae_int32x2));
 			}
 		}
 	}