1
0
mirror of https://github.com/RPCS3/llvm-mirror.git synced 2024-11-23 19:23:23 +01:00
llvm-mirror/test/CodeGen/AVR/software-mul.ll
Dylan McKay e48d05bbd3 [AVR] Expand 8/16-bit multiplication to libcalls on MCUs that don't have hardware MUL
This change modifies the LLVM ISel lowering settings so that
8-bit/16-bit multiplication is expanded to calls into the compiler
runtime library if the MCU being targeted does not support
multiplication in hardware.

Before this, MUL instructions would be generated on CPUs like the
ATtiny85, triggering a CPU reset due to an illegal instruction at
runtime.

First raised in https://github.com/avr-rust/rust/issues/124.

llvm-svn: 351523
2019-01-18 06:10:41 +00:00

29 lines
741 B
LLVM

; RUN: llc -mattr=avr6,-mul < %s -march=avr | FileCheck %s
; RUN: llc -mcpu=attiny85 < %s -march=avr | FileCheck %s
; RUN: llc -mcpu=ata5272 < %s -march=avr | FileCheck %s
; RUN: llc -mcpu=attiny861a < %s -march=avr | FileCheck %s
; RUN: llc -mcpu=at90usb82 < %s -march=avr | FileCheck %s
; Tests lowering of multiplication to compiler support routines.
; CHECK-LABEL: mul8:
define i8 @mul8(i8 %a, i8 %b) {
; CHECK: mov r25, r24
; CHECK: mov r24, r22
; CHECK: mov r22, r25
; CHECK: call __mulqi3
%mul = mul i8 %b, %a
ret i8 %mul
}
; CHECK-LABEL: mul16:
define i16 @mul16(i16 %a, i16 %b) {
; CHECK: movw r18, r24
; CHECK: movw r24, r22
; CHECK: movw r22, r18
; CHECK: call __mulhi3
%mul = mul nsw i16 %b, %a
ret i16 %mul
}