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; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
; RUN: llc -O3 < %s -mtriple=riscv32 | FileCheck %s
; These tests demonstrate optimizations involving copies from VLENB.
define void @unused_copy_is_dead() {
; CHECK-LABEL: unused_copy_is_dead:
; CHECK: # %bb.0: # %entry
; CHECK-NEXT: ret
entry:
call i32 @llvm.read_register.i32(metadata !0)
ret void
}
define i32 @simple_cse() {
; CHECK-LABEL: simple_cse:
; CHECK: # %bb.0: # %entry
; CHECK-NEXT: csrr a0, vlenb
; CHECK-NEXT: sub a0, a0, a0
; CHECK-NEXT: ret
entry:
%v1 = call i32 @llvm.read_register.i32(metadata !0)
%v2 = call i32 @llvm.read_register.i32(metadata !0)
%sub = sub i32 %v1, %v2
ret i32 %sub
}
define i32 @sink_to_use_branch(i1 %c) {
; CHECK-LABEL: sink_to_use_branch:
; CHECK: # %bb.0: # %entry
; CHECK-NEXT: andi a0, a0, 1
; CHECK-NEXT: beqz a0, .LBB2_2
; CHECK-NEXT: # %bb.1: # %used
; CHECK-NEXT: csrr a0, vlenb
; CHECK-NEXT: .LBB2_2: # %unused
; CHECK-NEXT: ret
entry:
%v1 = call i32 @llvm.read_register.i32(metadata !0)
br i1 %c, label %used, label %unused
used:
ret i32 %v1
unused:
ret i32 0
}
define i32 @sink_to_use_call() {
; CHECK-LABEL: sink_to_use_call:
; CHECK: # %bb.0: # %entry
; CHECK-NEXT: addi sp, sp, -16
; CHECK-NEXT: .cfi_def_cfa_offset 16
; CHECK-NEXT: sw ra, 12(sp) # 4-byte Folded Spill
; CHECK-NEXT: sw s0, 8(sp) # 4-byte Folded Spill
; CHECK-NEXT: .cfi_offset ra, -4
; CHECK-NEXT: .cfi_offset s0, -8
; CHECK-NEXT: csrr s0, vlenb
; CHECK-NEXT: call unknown
; CHECK-NEXT: mv a0, s0
; CHECK-NEXT: lw ra, 12(sp) # 4-byte Folded Reload
; CHECK-NEXT: lw s0, 8(sp) # 4-byte Folded Reload
; CHECK-NEXT: addi sp, sp, 16
; CHECK-NEXT: ret
entry:
%v1 = call i32 @llvm.read_register.i32(metadata !0)
call void @unknown() ; maythrow
ret i32 %v1
}
define void @machine_licm() {
; CHECK-LABEL: machine_licm:
; CHECK: # %bb.0: # %entry
; CHECK-NEXT: addi sp, sp, -16
; CHECK-NEXT: .cfi_def_cfa_offset 16
; CHECK-NEXT: sw ra, 12(sp) # 4-byte Folded Spill
; CHECK-NEXT: sw s0, 8(sp) # 4-byte Folded Spill
; CHECK-NEXT: .cfi_offset ra, -4
; CHECK-NEXT: .cfi_offset s0, -8
; CHECK-NEXT: csrr s0, vlenb
; CHECK-NEXT: .LBB4_1: # %loop
; CHECK-NEXT: # =>This Inner Loop Header: Depth=1
; CHECK-NEXT: mv a0, s0
; CHECK-NEXT: call use
; CHECK-NEXT: j .LBB4_1
entry:
br label %loop
loop:
%v1 = call i32 @llvm.read_register.i32(metadata !0)
call void @use(i32 %v1)
br label %loop
}
declare i32 @llvm.read_register.i32(metadata) nounwind
declare void @unknown()
declare void @use(i32)
!0 = !{!"vlenb"}
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