llvm-project/llvm/test/CodeGen/AArch64/shift-mod.ll

35 lines
830 B
LLVM
Raw Normal View History

; RUN: llc -mtriple=aarch64 < %s | FileCheck %s
; Check that we optimize out AND instructions and ADD/SUB instructions
; modulo the shift size to take advantage of the implicit mod done on
; the shift amount value by the variable shift/rotate instructions.
define i32 @test1(i32 %x, i64 %y) {
; CHECK-LABEL: test1:
; CHECK-NOT: and
; CHECK: lsr
%sh_prom = trunc i64 %y to i32
%shr = lshr i32 %x, %sh_prom
ret i32 %shr
}
define i64 @test2(i32 %x, i64 %y) {
; CHECK-LABEL: test2:
; CHECK-NOT: orr
; CHECK-NOT: sub
; CHECK: neg
; CHECK: asr
%sub9 = sub nsw i32 64, %x
%sh_prom12.i = zext i32 %sub9 to i64
%shr.i = ashr i64 %y, %sh_prom12.i
ret i64 %shr.i
}
define i64 @test3(i64 %x, i64 %y) {
; CHECK-LABEL: test3:
; CHECK-NOT: add
; CHECK: lsl
%add = add nsw i64 64, %x
%shl = shl i64 %y, %add
ret i64 %shl
}