[libclc] libclc: Add subgroup scan functions (PR #188828)

[Wenju He via cfe-commits]

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@@ -0,0 +1,100 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "clc/clc_convert.h"
+#include "clc/math/clc_fmax.h"
+#include "clc/math/clc_fmin.h"
+#include "clc/shared/clc_max.h"
+#include "clc/shared/clc_min.h"
+#include "clc/subgroup/clc_sub_group_broadcast.h"
+#include "clc/subgroup/clc_sub_group_scan.h"
+#include "clc/subgroup/clc_subgroup.h"
+
+#define QUAD_PERM (1 << 15)
+
+// The first basic swizzle mode (when offset[15] == 1) allows full data sharing
+// between a group of 4 consecutive threads.
+#define SWIZZLE_QUAD_PERM(S0, S1, S2, S3)                                      \
+  (uint)(QUAD_PERM | (S3 << 6) | (S2 << 4) | (S1 << 2) | S0)
+
+#define SWIZZLE_PAIRWISE(XOR_MASK, OR_MASK, AND_MASK)                          \
+  (uint)((XOR_MASK << 10) | (OR_MASK << 5) | AND_MASK)
+
+#define SWIZZLE_BCASTX2_LANE0 SWIZZLE_PAIRWISE(0x00, 0x00, 0x1e)
+#define SWIZZLE_BCASTX4_LANE1 SWIZZLE_PAIRWISE(0x00, 0x01, 0x1c)
+#define SWIZZLE_BCASTX8_LANE3 SWIZZLE_PAIRWISE(0x00, 0x03, 0x18)
+#define SWIZZLE_BCASTX16_LANE7 SWIZZLE_PAIRWISE(0x00, 0x07, 0x10)
+#define SWIZZLE_BCASTX32_LANE15 SWIZZLE_PAIRWISE(0x00, 0x0f, 0x00)
+
+#define __CLC_BODY "clc_amdgpu_ds_swizzle.inc"
+#include "clc/integer/gentype.inc"
+
+#define __CLC_BODY "clc_amdgpu_ds_swizzle.inc"
+#include "clc/math/gentype.inc"
+
+//------------------------------------------------------------------------------
+//  Integer and fp add
+//------------------------------------------------------------------------------
+
+#define __CLC_FUNCTION_INCLUSIVE __clc_sub_group_scan_inclusive_add
+#define __CLC_FUNCTION_EXCLUSIVE __clc_sub_group_scan_exclusive_add
+#define __CLC_FUNCTION_IMPL(x, y) ((x) + (y))
+#define __CLC_SUBGROUP_SCAN_ID_VAL (__CLC_GENTYPE)0
+#define __CLC_BODY "clc_sub_group_scan.inc"
+#include "clc/integer/gentype.inc"
+
+#define __CLC_BODY "clc_sub_group_scan.inc"
+#include "clc/math/gentype.inc"
+
+#undef __CLC_FUNCTION_INCLUSIVE
+#undef __CLC_FUNCTION_EXCLUSIVE
+#undef __CLC_FUNCTION_IMPL
+#undef __CLC_SUBGROUP_SCAN_ID_VAL
+
+//------------------------------------------------------------------------------
+//  Integer and fp min
+//------------------------------------------------------------------------------
+
+#define __CLC_FUNCTION_INCLUSIVE __clc_sub_group_scan_inclusive_min
+#define __CLC_FUNCTION_EXCLUSIVE __clc_sub_group_scan_exclusive_min
+#define __CLC_FUNCTION_IMPL(x, y) __clc_min(x, y)
+#define __CLC_SUBGROUP_SCAN_ID_VAL __CLC_GEN_MAX
+#define __CLC_BODY "clc_sub_group_scan.inc"
+#include "clc/integer/gentype.inc"
+#undef __CLC_FUNCTION_IMPL
+
+#define __CLC_FUNCTION_IMPL(x, y) __clc_fmin(x, y)
+#define __CLC_BODY "clc_sub_group_scan.inc"
+#include "clc/math/gentype.inc"
+#undef __CLC_FUNCTION_IMPL
+#undef __CLC_FUNCTION_INCLUSIVE
+#undef __CLC_FUNCTION_EXCLUSIVE
+#undef __CLC_SUBGROUP_SCAN_ID_VAL
+
+//------------------------------------------------------------------------------
+//  Integer and fp max
+//------------------------------------------------------------------------------
+
+#define __CLC_FUNCTION_INCLUSIVE __clc_sub_group_scan_inclusive_max
+#define __CLC_FUNCTION_EXCLUSIVE __clc_sub_group_scan_exclusive_max
+#define __CLC_FUNCTION_IMPL(x, y) __clc_max(x, y)
+#define __CLC_SUBGROUP_SCAN_ID_VAL __CLC_GEN_MIN
+
+#define __CLC_BODY "clc_sub_group_scan.inc"
+#include "clc/integer/gentype.inc"
+#undef __CLC_FUNCTION_IMPL
+
+#define __CLC_FUNCTION_IMPL(x, y) __clc_fmax(x, y)
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wenju-he wrote:

same here, can re-use __clc_max

https://github.com/llvm/llvm-project/pull/188828