// license that can be found in the LICENSE file.

// Fold constant shift with extension.
(SRAI [c] (MOVBreg  x)) && c <   8 => (SRAI [56+c] (SLLI <typ.Int64> [56] x))
(SRAI [c] (MOVHreg  x)) && c <  16 => (SRAI [48+c] (SLLI <typ.Int64> [48] x))
(SRAI [c] (MOVWreg  x)) && c <  32 => (SRAI [32+c] (SLLI <typ.Int64> [32] x))
(SRLI [c] (MOVBUreg x)) && c <   8 => (SRLI [56+c] (SLLI <typ.UInt64> [56] x))

		return true
	}
	return false
}
func rewriteValueRISCV64latelower_OpRISCV64SRAI(v *Value) bool {
	v_0 := v.Args[0]
	b := v.Block
	typ := &b.Func.Config.Types
	// match: (SRAI [c] (MOVBreg x))
	// cond: c < 8
	// result: (SRAI [56+c] (SLLI <typ.Int64> [56] x))
	for {
		c := auxIntToInt64(v.AuxInt)
		if v_0.Op != OpRISCV64MOVBreg {
			break
		}
		x := v_0.Args[0]
		if !(c < 8) {
			break
		}

	SRLI	$64, X5, X6			// ERROR "immediate out of range 0 to 63"
	SRAI	$64, X5, X6			// ERROR "immediate out of range 0 to 63"
	RORI	$-1, X5, X6			// ERROR "immediate out of range 0 to 63"
	SLLI	$-1, X5, X6			// ERROR "immediate out of range 0 to 63"
	SRLI	$-1, X5, X6			// ERROR "immediate out of range 0 to 63"
	SRAI	$-1, X5, X6			// ERROR "immediate out of range 0 to 63"

	// ppc64x:"SRAD"
	// riscv64:"SRAI\t",-"OR",-"SLTIU"
	return v >> uint64(33)
}

func rshConst64x64Overflow32(v int32) int64 {
	// riscv64:"SRAIW",-"SLLI",-"SRAI\t"
	return int64(v) >> 32
}

func rshConst64x64Overflow16(v int16) int64 {
	// riscv64:"SLLI","SRAI",-"SRAIW"
	return int64(v) >> 16
}

func rshConst64x64Overflow8(v int8) int64 {
	// riscv64:"SLLI","SRAI",-"SRAIW"
	return int64(v) >> 8
}

(SRAI <t> [x] (MOVWreg  y)) && x >= 0 && x <= 31 => (SRAIW <t> [int64(x)] y)
(SRLI <t> [x] (MOVWUreg y)) && x >= 0 && x <= 31 => (SRLIW <t> [int64(x)] y)

// Replace right shifts that exceed size of signed type.
(SRAI <t> [x] (MOVBreg y)) && x >=  8 => (SRAI  [63] (SLLI <t> [56] y))
(SRAI <t> [x] (MOVHreg y)) && x >= 16 => (SRAI  [63] (SLLI <t> [48] y))
(SRAI <t> [x] (MOVWreg y)) && x >= 32 => (SRAIW [31] y)

package riscv

import "cmd/internal/obj"

var Anames = []string{
	obj.A_ARCHSPECIFIC: "ADDI",
	"SLTI",
	"SLTIU",
	"ANDI",
	"ORI",
	"XORI",
	"SLLI",
	"SRLI",
	"SRAI",
	"LUI",
	"AUIPC",
	"ADD",
	"SLT",
	"SLTU",
	"AND",
	"OR",
	"XOR",
	"SLL",
	"SRL",
	"SUB",
	"SRA",
	"JAL",
	"JALR",
	"BEQ",
	"BNE",
	"BLT",
	"BLTU",
	"BGE",
	"BGEU",

	XORI	$1, X5					// 93c21200
	XORI	$2048, X5				// b71f00009b8f0f80b3c2f201

	SLLI	$1, X5, X6				// 13931200
	SLLI	$1, X5					// 93921200
	SRLI	$1, X5, X6				// 13d31200
	SRLI	$1, X5					// 93d21200
	SRAI	$1, X5, X6				// 13d31240
	SRAI	$1, X5					// 93d21240

	ADD	X6, X5, X7				// b3836200
	ADD	X5, X6					// 33035300
	ADD	$2047, X5, X6				// 1383f27f
	ADD	$-2048, X5, X6				// 13830280
	ADD	$2047, X5				// 9382f27f

		{name: "SLLIW", argLength: 1, reg: gp11, asm: "SLLIW", aux: "Int64"}, // arg0 << auxint, shift amount 0-31, logical left shift of 32 bit value, sign extended to 64 bits
		{name: "SRAI", argLength: 1, reg: gp11, asm: "SRAI", aux: "Int64"},   // arg0 >> auxint, shift amount 0-63, arithmetic right shift

		}
		v.reset(OpRISCV64SRAIW)
		v.Type = t
		v.AuxInt = int64ToAuxInt(int64(x))
		v.AddArg(y)
		return true
	}
	// match: (SRAI <t> [x] (MOVBreg y))
	// cond: x >= 8
	// result: (SRAI [63] (SLLI <t> [56] y))
	for {
		t := v.Type
		x := auxIntToInt64(v.AuxInt)
		if v_0.Op != OpRISCV64MOVBreg {
			break
		}
		y := v_0.Args[0]
		if !(x >= 8) {
			break
		}

				// Use SEXTB or SEXTH to extend.
				ins.as, ins.rs1, ins.rs2 = ASEXTB, uint32(p.From.Reg), obj.REG_NONE
				if p.As == AMOVH {
					ins.as = ASEXTH
				}
			} else {
				// Use SLLI/SRAI sequence to extend.
				ins.as, ins.rs1, ins.rs2 = ASLLI, uint32(p.From.Reg), obj.REG_NONE
				if p.As == AMOVB {
					ins.imm = 56
				} else if p.As == AMOVH {
					ins.imm = 48
				}