/*
 * Copyright © 2012 Intel Corporation
 * SPDX-License-Identifier: MIT
 */

#include <stdlib.h>
#include <stdio.h>
#include <stdbool.h>
#include "util/ralloc.h"
#include "brw_disasm.h"
#include "brw_eu.h"

#include <gtest/gtest.h>

struct CompactParams {
   unsigned verx10;
   unsigned align;
};

std::string
get_compact_params_name(const testing::TestParamInfo<CompactParams> p)
{
   CompactParams params = p.param;
   std::stringstream ss;
   ss << params.verx10 << "_";
   switch (params.align) {
   case BRW_ALIGN_1:
      ss << "Align_1";
      break;
   case BRW_ALIGN_16:
      ss << "Align_16";
      break;
   default:
      UNREACHABLE("invalid align");
   }
   return ss.str();
}

static bool
test_compact_instruction(struct brw_codegen *p, brw_eu_inst src)
{
   brw_eu_compact_inst dst;
   memset(&dst, 0xd0, sizeof(dst));

   if (brw_try_compact_instruction(p->isa, &dst, &src)) {
      brw_eu_inst uncompacted;

      brw_uncompact_instruction(p->isa, &uncompacted, &dst);
      if (memcmp(&uncompacted, &src, sizeof(src))) {
	 brw_debug_compact_uncompact(p->isa, &src, &uncompacted);
	 return false;
      }
   } else {
      brw_eu_compact_inst unchanged;
      memset(&unchanged, 0xd0, sizeof(unchanged));
      /* It's not supposed to change dst unless it compacted. */
      if (memcmp(&unchanged, &dst, sizeof(dst))) {
	 fprintf(stderr, "Failed to compact, but dst changed\n");
	 fprintf(stderr, "  Instruction: ");
	 brw_disassemble_inst(stderr, p->isa, &src, false, 0, NULL);
	 return false;
      }
   }

   return true;
}

/**
 * When doing fuzz testing, pad bits won't round-trip.
 *
 * This sort of a superset of skip_bit, which is testing for changing bits that
 * aren't worth testing for fuzzing.  We also just want to clear bits that
 * become meaningless once fuzzing twiddles a related bit.
 */
static void
clear_pad_bits(const struct brw_isa_info *isa, brw_eu_inst *inst)
{
   const struct intel_device_info *devinfo = isa->devinfo;

   if (brw_eu_inst_opcode(isa, inst) != BRW_OPCODE_SEND &&
       brw_eu_inst_opcode(isa, inst) != BRW_OPCODE_SENDC &&
       brw_eu_inst_src0_reg_file(devinfo, inst) != IMM &&
       brw_eu_inst_src1_reg_file(devinfo, inst) != IMM) {
      brw_eu_inst_set_bits(inst, 127, 111, 0);
   }
}

static bool
skip_bit(const struct brw_isa_info *isa, brw_eu_inst *src, int bit)
{
   const struct intel_device_info *devinfo = isa->devinfo;

   /* pad bit */
   if (bit == 7)
      return true;

   /* The compact bit -- uncompacted can't have it set. */
   if (bit == 29)
      return true;

   if (is_3src(isa, brw_eu_inst_opcode(isa, src))) {
      if (bit == 127)
         return true;
   } else {
      if (bit == 47)
         return true;

      if (bit == 11)
         return true;

      if (bit == 95)
         return true;
   }

   /* sometimes these are pad bits. */
   if (brw_eu_inst_opcode(isa, src) != BRW_OPCODE_SEND &&
       brw_eu_inst_opcode(isa, src) != BRW_OPCODE_SENDC &&
       brw_eu_inst_src0_reg_file(devinfo, src) != IMM &&
       brw_eu_inst_src1_reg_file(devinfo, src) != IMM &&
       bit >= 121) {
      return true;
   }

   return false;
}

static bool
test_fuzz_compact_instruction(struct brw_codegen *p, brw_eu_inst src)
{
   for (int bit0 = 0; bit0 < 128; bit0++) {
      if (skip_bit(p->isa, &src, bit0))
	 continue;

      for (int bit1 = 0; bit1 < 128; bit1++) {
         brw_eu_inst instr = src;
	 uint64_t *bits = instr.data;

         if (skip_bit(p->isa, &src, bit1))
	    continue;

	 bits[bit0 / 64] ^= (1ull << (bit0 & 63));
	 bits[bit1 / 64] ^= (1ull << (bit1 & 63));

         clear_pad_bits(p->isa, &instr);

         if (!brw_validate_instruction(p->isa, &instr, 0, sizeof(brw_eu_inst), NULL))
            continue;

	 if (!test_compact_instruction(p, instr)) {
	    printf("  twiddled bits for fuzzing %d, %d\n", bit0, bit1);
	    return false;
	 }
      }
   }

   return true;
}

class CompactTestFixture : public testing::TestWithParam<CompactParams> {
protected:
   virtual void SetUp() {
      CompactParams params = GetParam();
      mem_ctx = ralloc_context(NULL);
      devinfo = rzalloc(mem_ctx, intel_device_info);
      p = rzalloc(mem_ctx, brw_codegen);

      devinfo->verx10 = params.verx10;
      devinfo->ver = devinfo->verx10 / 10;

      brw_init_isa_info(&isa, devinfo);
      brw_init_codegen(&isa, p, p);
      brw_set_default_predicate_control(p, BRW_PREDICATE_NONE);
      brw_set_default_access_mode(p, params.align);
   };

   virtual void TearDown() {
      EXPECT_EQ(p->nr_insn, 1);
      EXPECT_TRUE(test_compact_instruction(p, p->store[0]));
      EXPECT_TRUE(test_fuzz_compact_instruction(p, p->store[0]));

      ralloc_free(mem_ctx);
   };

   void *mem_ctx;
   struct brw_isa_info isa;
   intel_device_info *devinfo;
   brw_codegen *p;
};

class Instructions : public CompactTestFixture {};

INSTANTIATE_TEST_SUITE_P(
   CompactTest,
   Instructions,
   testing::Values(
      CompactParams{ 90,  BRW_ALIGN_1 }, CompactParams{ 90, BRW_ALIGN_16 },
      CompactParams{ 110, BRW_ALIGN_1 },
      CompactParams{ 120, BRW_ALIGN_1 },
      CompactParams{ 125, BRW_ALIGN_1 },
      CompactParams{ 200, BRW_ALIGN_1 },
      CompactParams{ 300, BRW_ALIGN_1 }
   ),
   get_compact_params_name);

TEST_P(Instructions, ADD_GRF_GRF_GRF)
{
   struct brw_reg g0 = brw_vec8_grf(0, 0);
   struct brw_reg g2 = brw_vec8_grf(2, 0);
   struct brw_reg g4 = brw_vec8_grf(4, 0);

   brw_ADD(p, g0, g2, g4);
}

TEST_P(Instructions, ADD_GRF_GRF_IMM)
{
   struct brw_reg g0 = brw_vec8_grf(0, 0);
   struct brw_reg g2 = brw_vec8_grf(2, 0);

   brw_ADD(p, g0, g2, brw_imm_f(1.0));
}

TEST_P(Instructions, ADD_GRF_GRF_IMM_d)
{
   struct brw_reg g0 = retype(brw_vec8_grf(0, 0), BRW_TYPE_D);
   struct brw_reg g2 = retype(brw_vec8_grf(2, 0), BRW_TYPE_D);

   brw_ADD(p, g0, g2, brw_imm_d(1));
}

TEST_P(Instructions, MOV_GRF_GRF)
{
   struct brw_reg g0 = brw_vec8_grf(0, 0);
   struct brw_reg g2 = brw_vec8_grf(2, 0);

   brw_MOV(p, g0, g2);
}

TEST_P(Instructions, ADD_vec1_GRF_GRF_GRF)
{
   struct brw_reg g0 = brw_vec1_grf(0, 0);
   struct brw_reg g2 = brw_vec1_grf(2, 0);
   struct brw_reg g4 = brw_vec1_grf(4, 0);

   brw_ADD(p, g0, g2, g4);
}

TEST_P(Instructions, f0_0_MOV_GRF_GRF)
{
   struct brw_reg g0 = brw_vec8_grf(0, 0);
   struct brw_reg g2 = brw_vec8_grf(2, 0);

   brw_push_insn_state(p);
   brw_set_default_predicate_control(p, BRW_PREDICATE_NORMAL);
   brw_MOV(p, g0, g2);
   brw_pop_insn_state(p);
}

/* The handling of f0.1 vs f0.0 changes between gfx6 and gfx7.  Explicitly test
 * it, so that we run the fuzzing can run over all the other bits that might
 * interact with it.
 */
TEST_P(Instructions, f0_1_MOV_GRF_GRF)
{
   struct brw_reg g0 = brw_vec8_grf(0, 0);
   struct brw_reg g2 = brw_vec8_grf(2, 0);

   brw_push_insn_state(p);
   brw_set_default_predicate_control(p, BRW_PREDICATE_NORMAL);
   brw_eu_inst *mov = brw_MOV(p, g0, g2);
   brw_eu_inst_set_flag_subreg_nr(p->devinfo, mov, 1);
   brw_pop_insn_state(p);
}
