compiler-rt/lib/builtins/riscv/save.S

//===-- save.S - save up to 12 callee-saved registers ---------------------===//
//
// 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
//
//===----------------------------------------------------------------------===//
//
// Multiple entry points depending on number of registers to save
//
//===----------------------------------------------------------------------===//

// The entry points are grouped up into 2s for rv64 and 4s for rv32 since this
// is the minimum grouping which will maintain the required 16-byte stack
// alignment.

  .text

#if __riscv_xlen == 32

  .globl  __riscv_save_12
  .type   __riscv_save_12,@function
__riscv_save_12:
  addi   sp, sp, -64
  mv     t1, zero
  sw     s11, 12(sp)
  j      .Lriscv_save_11_8

  .globl  __riscv_save_11
  .type   __riscv_save_11,@function
  .globl  __riscv_save_10
  .type   __riscv_save_10,@function
  .globl  __riscv_save_9
  .type   __riscv_save_9,@function
  .globl  __riscv_save_8
  .type   __riscv_save_8,@function
__riscv_save_11:
__riscv_save_10:
__riscv_save_9:
__riscv_save_8:
  addi   sp, sp, -64
  li     t1, 16
.Lriscv_save_11_8:
  sw     s10, 16(sp)
  sw     s9,  20(sp)
  sw     s8,  24(sp)
  sw     s7,  28(sp)
  j      .Lriscv_save_7_4

  .globl  __riscv_save_7
  .type   __riscv_save_7,@function
  .globl  __riscv_save_6
  .type   __riscv_save_6,@function
  .globl  __riscv_save_5
  .type   __riscv_save_5,@function
  .globl  __riscv_save_4
  .type   __riscv_save_4,@function
__riscv_save_7:
__riscv_save_6:
__riscv_save_5:
__riscv_save_4:
  addi   sp, sp, -64
  li     t1, 32
.Lriscv_save_7_4:
  sw     s6, 32(sp)
  sw     s5, 36(sp)
  sw     s4, 40(sp)
  sw     s3, 44(sp)
  sw     s2, 48(sp)
  sw     s1, 52(sp)
  sw     s0, 56(sp)
  sw     ra, 60(sp)
  add    sp, sp, t1
  jr     t0

  .globl  __riscv_save_3
  .type   __riscv_save_3,@function
  .globl  __riscv_save_2
  .type   __riscv_save_2,@function
  .globl  __riscv_save_1
  .type   __riscv_save_1,@function
  .globl  __riscv_save_0
  .type   __riscv_save_0,@function
__riscv_save_3:
__riscv_save_2:
__riscv_save_1:
__riscv_save_0:
  addi    sp, sp, -16
  sw      s2,  0(sp)
  sw      s1,  4(sp)
  sw      s0,  8(sp)
  sw      ra,  12(sp)
  jr      t0

#elif __riscv_xlen == 64

  .globl  __riscv_save_12
  .type   __riscv_save_12,@function
__riscv_save_12:
  addi   sp, sp, -112
  mv     t1, zero
  sd     s11, 8(sp)
  j      .Lriscv_save_11_10

  .globl  __riscv_save_11
  .type   __riscv_save_11,@function
  .globl  __riscv_save_10
  .type   __riscv_save_10,@function
__riscv_save_11:
__riscv_save_10:
  addi   sp, sp, -112
  li     t1, 16
.Lriscv_save_11_10:
  sd     s10, 16(sp)
  sd     s9,  24(sp)
  j      .Lriscv_save_9_8

  .globl  __riscv_save_9
  .type   __riscv_save_9,@function
  .globl  __riscv_save_8
  .type   __riscv_save_8,@function
__riscv_save_9:
__riscv_save_8:
  addi   sp, sp, -112
  li     t1, 32
.Lriscv_save_9_8:
  sd     s8,  32(sp)
  sd     s7,  40(sp)
  j      .Lriscv_save_7_6

  .globl  __riscv_save_7
  .type   __riscv_save_7,@function
  .globl  __riscv_save_6
  .type   __riscv_save_6,@function
__riscv_save_7:
__riscv_save_6:
  addi   sp, sp, -112
  li     t1, 48
.Lriscv_save_7_6:
  sd     s6,  48(sp)
  sd     s5,  56(sp)
  j      .Lriscv_save_5_4

  .globl  __riscv_save_5
  .type   __riscv_save_5,@function
  .globl  __riscv_save_4
  .type   __riscv_save_4,@function
__riscv_save_5:
__riscv_save_4:
  addi   sp, sp, -112
  li     t1, 64
.Lriscv_save_5_4:
  sd     s4, 64(sp)
  sd     s3, 72(sp)
  j      .Lriscv_save_3_2

  .globl  __riscv_save_3
  .type   __riscv_save_3,@function
  .globl  __riscv_save_2
  .type   __riscv_save_2,@function
__riscv_save_3:
__riscv_save_2:
  addi   sp, sp, -112
  li     t1, 80
.Lriscv_save_3_2:
  sd     s2, 80(sp)
  sd     s1, 88(sp)
  sd     s0, 96(sp)
  sd     ra, 104(sp)
  add    sp, sp, t1
  jr     t0

  .globl  __riscv_save_1
  .type   __riscv_save_1,@function
  .globl  __riscv_save_0
  .type   __riscv_save_0,@function
__riscv_save_1:
__riscv_save_0:
  addi   sp, sp, -16
  sd     s0, 0(sp)
  sd     ra, 8(sp)
  jr     t0

#else
# error "xlen must be 32 or 64 for save-restore implementation
#endif