llvm/test/CodeGen/RISCV/rem.ll
Alex Bradbury 1efb7b6d36 [RISCV] Introduce codegen patterns for RV64M-only instructions
As discussed on llvm-dev
<http://lists.llvm.org/pipermail/llvm-dev/2018-December/128497.html>, we have
to be careful when trying to select the *w RV64M instructions. i32 is not a
legal type for RV64 in the RISC-V backend, so operations have been promoted by
the time they reach instruction selection. Information about whether the
operation was originally a 32-bit operations has been lost, and it's easy to
write incorrect patterns.

Similarly to the variable 32-bit shifts, a DAG combine on ANY_EXTEND will
produce a SIGN_EXTEND if this is likely to result in sdiv/udiv/urem being
selected (and so save instructions to sext/zext the input operands).

Differential Revision: https://reviews.llvm.org/D53230


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@350993 91177308-0d34-0410-b5e6-96231b3b80d8
2019-01-12 07:43:06 +00:00

80 lines
2.1 KiB
LLVM

; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
; RUN: llc -mtriple=riscv32 -verify-machineinstrs < %s \
; RUN: | FileCheck -check-prefix=RV32I %s
; RUN: llc -mtriple=riscv32 -mattr=+m -verify-machineinstrs < %s \
; RUN: | FileCheck -check-prefix=RV32IM %s
; RUN: llc -mtriple=riscv64 -verify-machineinstrs < %s \
; RUN: | FileCheck -check-prefix=RV64I %s
; RUN: llc -mtriple=riscv64 -mattr=+m -verify-machineinstrs < %s \
; RUN: | FileCheck -check-prefix=RV64IM %s
define i32 @urem(i32 %a, i32 %b) nounwind {
; RV32I-LABEL: urem:
; RV32I: # %bb.0:
; RV32I-NEXT: addi sp, sp, -16
; RV32I-NEXT: sw ra, 12(sp)
; RV32I-NEXT: call __umodsi3
; RV32I-NEXT: lw ra, 12(sp)
; RV32I-NEXT: addi sp, sp, 16
; RV32I-NEXT: ret
;
; RV32IM-LABEL: urem:
; RV32IM: # %bb.0:
; RV32IM-NEXT: remu a0, a0, a1
; RV32IM-NEXT: ret
;
; RV64I-LABEL: urem:
; RV64I: # %bb.0:
; RV64I-NEXT: addi sp, sp, -16
; RV64I-NEXT: sd ra, 8(sp)
; RV64I-NEXT: slli a0, a0, 32
; RV64I-NEXT: srli a0, a0, 32
; RV64I-NEXT: slli a1, a1, 32
; RV64I-NEXT: srli a1, a1, 32
; RV64I-NEXT: call __umoddi3
; RV64I-NEXT: ld ra, 8(sp)
; RV64I-NEXT: addi sp, sp, 16
; RV64I-NEXT: ret
;
; RV64IM-LABEL: urem:
; RV64IM: # %bb.0:
; RV64IM-NEXT: remuw a0, a0, a1
; RV64IM-NEXT: ret
%1 = urem i32 %a, %b
ret i32 %1
}
define i32 @srem(i32 %a, i32 %b) nounwind {
; RV32I-LABEL: srem:
; RV32I: # %bb.0:
; RV32I-NEXT: addi sp, sp, -16
; RV32I-NEXT: sw ra, 12(sp)
; RV32I-NEXT: call __modsi3
; RV32I-NEXT: lw ra, 12(sp)
; RV32I-NEXT: addi sp, sp, 16
; RV32I-NEXT: ret
;
; RV32IM-LABEL: srem:
; RV32IM: # %bb.0:
; RV32IM-NEXT: rem a0, a0, a1
; RV32IM-NEXT: ret
;
; RV64I-LABEL: srem:
; RV64I: # %bb.0:
; RV64I-NEXT: addi sp, sp, -16
; RV64I-NEXT: sd ra, 8(sp)
; RV64I-NEXT: sext.w a0, a0
; RV64I-NEXT: sext.w a1, a1
; RV64I-NEXT: call __moddi3
; RV64I-NEXT: ld ra, 8(sp)
; RV64I-NEXT: addi sp, sp, 16
; RV64I-NEXT: ret
;
; RV64IM-LABEL: srem:
; RV64IM: # %bb.0:
; RV64IM-NEXT: remw a0, a0, a1
; RV64IM-NEXT: ret
%1 = srem i32 %a, %b
ret i32 %1
}