llvm/test/CodeGen/RISCV/rvv/vfirst-byte-compare-index.ll

; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 5
; RUN: llc -mtriple=riscv64 -mattr=+v < %s | FileCheck %s

; Testing VFIRST patterns related to llvm/test/Transforms/LoopIdiom/RISCV/byte-compare-index.ll

define i32 @compare_bytes_simple(ptr %a, ptr %b, i32 signext %len, i32 signext %n) {
; CHECK-LABEL: compare_bytes_simple:
; CHECK:       # %bb.0: # %entry
; CHECK-NEXT:    addiw a4, a2, 1
; CHECK-NEXT:    bltu a3, a4, .LBB0_7
; CHECK-NEXT:  # %bb.1: # %mismatch_mem_check
; CHECK-NEXT:    slli a2, a4, 32
; CHECK-NEXT:    srli a2, a2, 32
; CHECK-NEXT:    slli a5, a3, 32
; CHECK-NEXT:    srli a5, a5, 32
; CHECK-NEXT:    add a6, a0, a2
; CHECK-NEXT:    add a7, a0, a5
; CHECK-NEXT:    srli a6, a6, 12
; CHECK-NEXT:    srli a7, a7, 12
; CHECK-NEXT:    bne a6, a7, .LBB0_7
; CHECK-NEXT:  # %bb.2: # %mismatch_mem_check
; CHECK-NEXT:    add a6, a1, a2
; CHECK-NEXT:    add a7, a1, a5
; CHECK-NEXT:    srli a6, a6, 12
; CHECK-NEXT:    srli a7, a7, 12
; CHECK-NEXT:    bne a6, a7, .LBB0_7
; CHECK-NEXT:  .LBB0_3: # %mismatch_vec_loop
; CHECK-NEXT:    # =>This Inner Loop Header: Depth=1
; CHECK-NEXT:    sub a4, a5, a2
; CHECK-NEXT:    vsetvli a4, a4, e8, m2, ta, ma
; CHECK-NEXT:    add a6, a0, a2
; CHECK-NEXT:    vle8.v v8, (a6)
; CHECK-NEXT:    add a6, a1, a2
; CHECK-NEXT:    vle8.v v10, (a6)
; CHECK-NEXT:    vmsne.vv v12, v8, v10
; CHECK-NEXT:    vfirst.m a7, v12
; CHECK-NEXT:    mv a6, a4
; CHECK-NEXT:    bltz a7, .LBB0_5
; CHECK-NEXT:  # %bb.4: # %mismatch_vec_loop
; CHECK-NEXT:    # in Loop: Header=BB0_3 Depth=1
; CHECK-NEXT:    mv a6, a7
; CHECK-NEXT:  .LBB0_5: # %mismatch_vec_loop
; CHECK-NEXT:    # in Loop: Header=BB0_3 Depth=1
; CHECK-NEXT:    sext.w a7, a6
; CHECK-NEXT:    bne a7, a4, .LBB0_11
; CHECK-NEXT:  # %bb.6: # %mismatch_vec_loop_inc
; CHECK-NEXT:    # in Loop: Header=BB0_3 Depth=1
; CHECK-NEXT:    add a2, a2, a4
; CHECK-NEXT:    bne a2, a5, .LBB0_3
; CHECK-NEXT:    j .LBB0_9
; CHECK-NEXT:  .LBB0_7: # %mismatch_loop
; CHECK-NEXT:    # =>This Inner Loop Header: Depth=1
; CHECK-NEXT:    slli a2, a4, 32
; CHECK-NEXT:    srli a2, a2, 32
; CHECK-NEXT:    add a5, a0, a2
; CHECK-NEXT:    lbu a5, 0(a5)
; CHECK-NEXT:    add a2, a1, a2
; CHECK-NEXT:    lbu a2, 0(a2)
; CHECK-NEXT:    bne a5, a2, .LBB0_10
; CHECK-NEXT:  # %bb.8: # %mismatch_loop_inc
; CHECK-NEXT:    # in Loop: Header=BB0_7 Depth=1
; CHECK-NEXT:    addiw a4, a4, 1
; CHECK-NEXT:    bne a3, a4, .LBB0_7
; CHECK-NEXT:  .LBB0_9: # %while.end
; CHECK-NEXT:    mv a0, a3
; CHECK-NEXT:    ret
; CHECK-NEXT:  .LBB0_10:
; CHECK-NEXT:    mv a0, a4
; CHECK-NEXT:    ret
; CHECK-NEXT:  .LBB0_11: # %mismatch_vec_loop_found
; CHECK-NEXT:    slli a6, a6, 32
; CHECK-NEXT:    srli a3, a6, 32
; CHECK-NEXT:    add a0, a2, a3
; CHECK-NEXT:    ret
entry:
  %0 = add i32 %len, 1
  br label %mismatch_min_it_check

mismatch_min_it_check:                            ; preds = %entry
  %1 = zext i32 %0 to i64
  %2 = zext i32 %n to i64
  %3 = icmp ule i32 %0, %n
  br i1 %3, label %mismatch_mem_check, label %mismatch_loop_pre

mismatch_mem_check:                               ; preds = %mismatch_min_it_check
  %4 = getelementptr i8, ptr %a, i64 %1
  %5 = getelementptr i8, ptr %b, i64 %1
  %6 = ptrtoint ptr %5 to i64
  %7 = ptrtoint ptr %4 to i64
  %8 = getelementptr i8, ptr %a, i64 %2
  %9 = getelementptr i8, ptr %b, i64 %2
  %10 = ptrtoint ptr %8 to i64
  %11 = ptrtoint ptr %9 to i64
  %12 = lshr i64 %7, 12
  %13 = lshr i64 %10, 12
  %14 = lshr i64 %6, 12
  %15 = lshr i64 %11, 12
  %16 = icmp ne i64 %12, %13
  %17 = icmp ne i64 %14, %15
  %18 = or i1 %16, %17
  br i1 %18, label %mismatch_loop_pre, label %mismatch_vec_loop_preheader

mismatch_vec_loop_preheader:                      ; preds = %mismatch_mem_check
  br label %mismatch_vec_loop

mismatch_vec_loop:                                ; preds = %mismatch_vec_loop_inc, %mismatch_vec_loop_preheader
  %mismatch_vector_index = phi i64 [ %1, %mismatch_vec_loop_preheader ], [ %25, %mismatch_vec_loop_inc ]
  %avl = sub nuw nsw i64 %2, %mismatch_vector_index
  %19 = call i32 @llvm.experimental.get.vector.length.i64(i64 %avl, i32 16, i1 true)
  %20 = getelementptr inbounds i8, ptr %a, i64 %mismatch_vector_index
  %lhs.load = call <vscale x 16 x i8> @llvm.vp.load.nxv16i8.p0(ptr %20, <vscale x 16 x i1> shufflevector (<vscale x 16 x i1> insertelement (<vscale x 16 x i1> poison, i1 true, i64 0), <vscale x 16 x i1> poison, <vscale x 16 x i32> zeroinitializer), i32 %19)
  %21 = getelementptr inbounds i8, ptr %b, i64 %mismatch_vector_index
  %rhs.load = call <vscale x 16 x i8> @llvm.vp.load.nxv16i8.p0(ptr %21, <vscale x 16 x i1> shufflevector (<vscale x 16 x i1> insertelement (<vscale x 16 x i1> poison, i1 true, i64 0), <vscale x 16 x i1> poison, <vscale x 16 x i32> zeroinitializer), i32 %19)
  %mismatch.cmp = call <vscale x 16 x i1> @llvm.vp.icmp.nxv16i8(<vscale x 16 x i8> %lhs.load, <vscale x 16 x i8> %rhs.load, metadata !"ne", <vscale x 16 x i1> shufflevector (<vscale x 16 x i1> insertelement (<vscale x 16 x i1> poison, i1 true, i64 0), <vscale x 16 x i1> poison, <vscale x 16 x i32> zeroinitializer), i32 %19)
  %22 = call i32 @llvm.vp.cttz.elts.i32.nxv16i1(<vscale x 16 x i1> %mismatch.cmp, i1 false, <vscale x 16 x i1> shufflevector (<vscale x 16 x i1> insertelement (<vscale x 16 x i1> poison, i1 true, i64 0), <vscale x 16 x i1> poison, <vscale x 16 x i32> zeroinitializer), i32 %19)
  %23 = icmp ne i32 %22, %19
  br i1 %23, label %mismatch_vec_loop_found, label %mismatch_vec_loop_inc

mismatch_vec_loop_inc:                            ; preds = %mismatch_vec_loop
  %24 = zext i32 %19 to i64
  %25 = add nuw nsw i64 %mismatch_vector_index, %24
  %26 = icmp ne i64 %25, %2
  br i1 %26, label %mismatch_vec_loop, label %mismatch_end

mismatch_vec_loop_found:                          ; preds = %mismatch_vec_loop
  %ctz = phi i32 [ %22, %mismatch_vec_loop ]
  %mismatch_vector_index1 = phi i64 [ %mismatch_vector_index, %mismatch_vec_loop ]
  %27 = zext i32 %ctz to i64
  %28 = add nuw nsw i64 %mismatch_vector_index1, %27
  %29 = trunc i64 %28 to i32
  br label %mismatch_end

mismatch_loop_pre:                                ; preds = %mismatch_mem_check, %mismatch_min_it_check
  br label %mismatch_loop

mismatch_loop:                                    ; preds = %mismatch_loop_inc, %mismatch_loop_pre
  %mismatch_index = phi i32 [ %0, %mismatch_loop_pre ], [ %36, %mismatch_loop_inc ]
  %30 = zext i32 %mismatch_index to i64
  %31 = getelementptr inbounds i8, ptr %a, i64 %30
  %32 = load i8, ptr %31, align 1
  %33 = getelementptr inbounds i8, ptr %b, i64 %30
  %34 = load i8, ptr %33, align 1
  %35 = icmp eq i8 %32, %34
  br i1 %35, label %mismatch_loop_inc, label %mismatch_end

mismatch_loop_inc:                                ; preds = %mismatch_loop
  %36 = add i32 %mismatch_index, 1
  %37 = icmp eq i32 %36, %n
  br i1 %37, label %mismatch_end, label %mismatch_loop

mismatch_end:                                     ; preds = %mismatch_loop_inc, %mismatch_loop, %mismatch_vec_loop_found, %mismatch_vec_loop_inc
  %mismatch_result = phi i32 [ %n, %mismatch_loop_inc ], [ %mismatch_index, %mismatch_loop ], [ %n, %mismatch_vec_loop_inc ], [ %29, %mismatch_vec_loop_found ]
  br i1 true, label %byte.compare, label %while.cond

while.cond:                                       ; preds = %mismatch_end, %while.body
  %len.addr = phi i32 [ %len, %mismatch_end ], [ %mismatch_result, %while.body ]
  %inc = add i32 %len.addr, 1
  %cmp.not = icmp eq i32 %mismatch_result, %n
  br i1 %cmp.not, label %while.end, label %while.body

while.body:                                       ; preds = %while.cond
  %idxprom = zext i32 %mismatch_result to i64
  %arrayidx = getelementptr inbounds i8, ptr %a, i64 %idxprom
  %38 = load i8, ptr %arrayidx, align 1
  %arrayidx2 = getelementptr inbounds i8, ptr %b, i64 %idxprom
  %39 = load i8, ptr %arrayidx2, align 1
  %cmp.not2 = icmp eq i8 %38, %39
  br i1 %cmp.not2, label %while.cond, label %while.end

byte.compare:                                     ; preds = %mismatch_end
  br label %while.end

while.end:                                        ; preds = %byte.compare, %while.body, %while.cond
  %inc.lcssa = phi i32 [ %mismatch_result, %while.body ], [ %mismatch_result, %while.cond ], [ %mismatch_result, %byte.compare ]
  ret i32 %inc.lcssa
}