Scalar implementations of QC8 GEMM/IGEMM microkernels

PiperOrigin-RevId: 382316395
diff --git a/src/qc8-igemm/gen/2x2-minmax-fp32-scalar-lrint.c b/src/qc8-igemm/gen/2x2-minmax-fp32-scalar-lrint.c
new file mode 100644
index 0000000..d0cde5d
--- /dev/null
+++ b/src/qc8-igemm/gen/2x2-minmax-fp32-scalar-lrint.c
@@ -0,0 +1,143 @@
+// Auto-generated file. Do not edit!
+//   Template: src/qs8-igemm/scalar.c.in
+//   Generator: tools/xngen
+//
+// Copyright 2021 Google LLC
+//
+// This source code is licensed under the BSD-style license found in the
+// LICENSE file in the root directory of this source tree.
+
+#include <assert.h>
+#include <math.h>
+
+#include <xnnpack/math.h>
+#include <xnnpack/gemm.h>
+
+
+void xnn_qc8_igemm_minmax_fp32_ukernel_2x2__scalar_lrint(
+    size_t mr,
+    size_t nc,
+    size_t kc,
+    size_t ks,
+    const int8_t**restrict a,
+    const void*restrict w,
+    int8_t*restrict c,
+    size_t cm_stride,
+    size_t cn_stride,
+    size_t a_offset,
+    const int8_t* zero,
+    const union xnn_qs8_minmax_params params[restrict XNN_MIN_ELEMENTS(1)])
+{
+  assert(mr != 0);
+  assert(mr <= 2);
+  assert(nc != 0);
+  assert(kc != 0);
+  assert(ks != 0);
+  assert(ks % (2 * sizeof(void*)) == 0);
+  assert(a != NULL);
+  assert(w != NULL);
+  assert(c != NULL);
+
+  int8_t* c0 = c;
+  int8_t* c1 = (int8_t*) ((uintptr_t) c0 + cm_stride);
+  if XNN_UNPREDICTABLE(mr != 2) {
+    c1 = c0;
+  }
+
+  do {
+    int32_t vacc0x0 = ((const int32_t*) w)[0];
+    int32_t vacc0x1 = ((const int32_t*) w)[1];
+    int32_t vacc1x0 = vacc0x0;
+    int32_t vacc1x1 = vacc0x1;
+    w = (const void*) ((uintptr_t) w + 2 * sizeof(int32_t));
+
+    size_t p = ks;
+    do {
+      const int8_t* restrict a0 = a[0];
+      assert(a0 != NULL);
+      if XNN_UNPREDICTABLE(a0 != zero) {
+        a0 = (const int8_t*) ((uintptr_t) a0 + a_offset);
+      }
+      const int8_t* restrict a1 = a[1];
+      assert(a1 != NULL);
+      if XNN_UNPREDICTABLE(a1 != zero) {
+        a1 = (const int8_t*) ((uintptr_t) a1 + a_offset);
+      }
+      a += 2;
+
+      size_t k = kc;
+      do {
+        const int32_t va0 = (int32_t) *a0++;
+        const int32_t va1 = (int32_t) *a1++;
+
+        const int32_t vb0 = ((const int8_t*) w)[0];
+        const int32_t vb1 = ((const int8_t*) w)[1];
+        w = (const void*) ((uintptr_t) w + 2 * sizeof(int8_t));
+
+        vacc0x0 += va0 * vb0;
+        vacc0x1 += va0 * vb1;
+        vacc1x0 += va1 * vb0;
+        vacc1x1 += va1 * vb1;
+
+        k -= sizeof(int8_t);
+      } while (k != 0);
+      p -= 2 * sizeof(void*);
+    } while (p != 0);
+
+    float vfpacc0x0 = (float) vacc0x0;
+    float vfpacc0x1 = (float) vacc0x1;
+    float vfpacc1x0 = (float) vacc1x0;
+    float vfpacc1x1 = (float) vacc1x1;
+
+    const float vscale0 = ((const float*) w)[0];
+    vfpacc0x0 *= vscale0;
+    vfpacc1x0 *= vscale0;
+    const float vscale1 = ((const float*) w)[1];
+    vfpacc0x1 *= vscale1;
+    vfpacc1x1 *= vscale1;
+    w = (const void*) ((const float*) w + 2);
+
+    long vrndacc0x0 = lrintf(vfpacc0x0);
+    long vrndacc0x1 = lrintf(vfpacc0x1);
+    long vrndacc1x0 = lrintf(vfpacc1x0);
+    long vrndacc1x1 = lrintf(vfpacc1x1);
+
+    const long voutput_min_less_zero_point = params->scalar_lrint.output_min_less_zero_point;
+    vrndacc0x0 = XNN_UNPREDICTABLE(vrndacc0x0 < voutput_min_less_zero_point) ? voutput_min_less_zero_point : vrndacc0x0;
+    vrndacc0x1 = XNN_UNPREDICTABLE(vrndacc0x1 < voutput_min_less_zero_point) ? voutput_min_less_zero_point : vrndacc0x1;
+    vrndacc1x0 = XNN_UNPREDICTABLE(vrndacc1x0 < voutput_min_less_zero_point) ? voutput_min_less_zero_point : vrndacc1x0;
+    vrndacc1x1 = XNN_UNPREDICTABLE(vrndacc1x1 < voutput_min_less_zero_point) ? voutput_min_less_zero_point : vrndacc1x1;
+
+    const long voutput_max_less_zero_point = params->scalar_lrint.output_max_less_zero_point;
+    vrndacc0x0 = XNN_UNPREDICTABLE(vrndacc0x0 > voutput_max_less_zero_point) ? voutput_max_less_zero_point : vrndacc0x0;
+    vrndacc0x1 = XNN_UNPREDICTABLE(vrndacc0x1 > voutput_max_less_zero_point) ? voutput_max_less_zero_point : vrndacc0x1;
+    vrndacc1x0 = XNN_UNPREDICTABLE(vrndacc1x0 > voutput_max_less_zero_point) ? voutput_max_less_zero_point : vrndacc1x0;
+    vrndacc1x1 = XNN_UNPREDICTABLE(vrndacc1x1 > voutput_max_less_zero_point) ? voutput_max_less_zero_point : vrndacc1x1;
+
+    const int32_t voutput_zero_point = params->scalar_lrint.output_zero_point;
+    int32_t vout0x0 = (int32_t) vrndacc0x0 + voutput_zero_point;
+    int32_t vout0x1 = (int32_t) vrndacc0x1 + voutput_zero_point;
+    int32_t vout1x0 = (int32_t) vrndacc1x0 + voutput_zero_point;
+    int32_t vout1x1 = (int32_t) vrndacc1x1 + voutput_zero_point;
+
+    if XNN_LIKELY(nc >= 2) {
+      c1[0] = (int8_t) vout1x0;
+      c1[1] = (int8_t) vout1x1;
+      c0[0] = (int8_t) vout0x0;
+      c0[1] = (int8_t) vout0x1;
+
+      c1 = (int8_t*) ((uintptr_t) c1 + cn_stride);
+      c0 = (int8_t*) ((uintptr_t) c0 + cn_stride);
+
+      a = (const int8_t**restrict) ((uintptr_t) a - ks);
+      nc -= 2;
+    } else {
+      if (nc & 1) {
+        c1[0] = (int8_t) vout1x0;
+        c0[0] = (int8_t) vout0x0;
+      }
+
+      nc = 0;
+    }
+  } while (nc != 0);
+}