llvm/test/Transforms/InstCombine/memset-1.ll

; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; Test that the memset library call simplifier works correctly.
;
; RUN: opt < %s -passes=instcombine -S | FileCheck %s

target datalayout = "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-a0:0:64-f80:128:128"

declare ptr @memset(ptr, i32, i32)
declare void @llvm.memset.p0.i32(ptr nocapture writeonly, i8, i32, i32, i1)
declare noalias ptr @malloc(i32) #1

; Check memset(mem1, val, size) -> llvm.memset(mem1, val, size, 1).

define ptr @test_simplify1(ptr %mem, i32 %val, i32 %size) {
; CHECK-LABEL: @test_simplify1(
; CHECK-NEXT:    [[TMP1:%.*]] = trunc i32 [[VAL:%.*]] to i8
; CHECK-NEXT:    call void @llvm.memset.p0.i32(ptr align 1 [[MEM:%.*]], i8 [[TMP1]], i32 [[SIZE:%.*]], i1 false)
; CHECK-NEXT:    ret ptr [[MEM]]
;
  %ret = call ptr @memset(ptr %mem, i32 %val, i32 %size)
  ret ptr %ret
}

define ptr @test_simplify1_tail(ptr %mem, i32 %val, i32 %size) {
; CHECK-LABEL: @test_simplify1_tail(
; CHECK-NEXT:    [[TMP1:%.*]] = trunc i32 [[VAL:%.*]] to i8
; CHECK-NEXT:    tail call void @llvm.memset.p0.i32(ptr align 1 [[MEM:%.*]], i8 [[TMP1]], i32 [[SIZE:%.*]], i1 false)
; CHECK-NEXT:    ret ptr [[MEM]]
;
  %ret = tail call ptr @memset(ptr %mem, i32 %val, i32 %size)
  ret ptr %ret
}

define ptr @test_simplify1_musttail(ptr %mem, i32 %val, i32 %size) {
; CHECK-LABEL: @test_simplify1_musttail(
; CHECK-NEXT:    [[RET:%.*]] = musttail call ptr @memset(ptr [[MEM:%.*]], i32 [[VAL:%.*]], i32 [[SIZE:%.*]])
; CHECK-NEXT:    ret ptr [[RET]]
;
  %ret = musttail call ptr @memset(ptr %mem, i32 %val, i32 %size)
  ret ptr %ret
}

; Malloc + memset pattern is now handled by DSE in a more general way.

define ptr @pr25892_lite(i32 %size) #0 {
; CHECK-LABEL: @pr25892_lite(
; CHECK-NEXT:    [[CALL1:%.*]] = call ptr @malloc(i32 [[SIZE:%.*]]) #[[ATTR0:[0-9]+]]
; CHECK-NEXT:    call void @llvm.memset.p0.i32(ptr align 1 [[CALL1]], i8 0, i32 [[SIZE]], i1 false) #[[ATTR0]]
; CHECK-NEXT:    ret ptr [[CALL1]]
;
  %call1 = call ptr @malloc(i32 %size) #1
  %call2 = call ptr @memset(ptr %call1, i32 0, i32 %size) #1
  ret ptr %call2
}

; A memset intrinsic should be handled similarly to a memset() libcall.
; Notice that malloc + memset pattern is now handled by DSE in a more general way.

define ptr @malloc_and_memset_intrinsic(i32 %n) #0 {
; CHECK-LABEL: @malloc_and_memset_intrinsic(
; CHECK-NEXT:    [[CALL:%.*]] = call ptr @malloc(i32 [[N:%.*]])
; CHECK-NEXT:    call void @llvm.memset.p0.i32(ptr align 1 [[CALL]], i8 0, i32 [[N]], i1 false)
; CHECK-NEXT:    ret ptr [[CALL]]
;
  %call = call ptr @malloc(i32 %n)
  call void @llvm.memset.p0.i32(ptr %call, i8 0, i32 %n, i32 1, i1 false)
  ret ptr %call
}

; This should not create a calloc and should not crash the compiler.
; Notice that malloc + memset pattern is now handled by DSE in a more general way.

define ptr @notmalloc_memset(i32 %size, ptr %notmalloc) {
; CHECK-LABEL: @notmalloc_memset(
; CHECK-NEXT:    [[CALL1:%.*]] = call ptr [[NOTMALLOC:%.*]](i32 [[SIZE:%.*]]) #[[ATTR0]]
; CHECK-NEXT:    call void @llvm.memset.p0.i32(ptr align 1 [[CALL1]], i8 0, i32 [[SIZE]], i1 false) #[[ATTR0]]
; CHECK-NEXT:    ret ptr [[CALL1]]
;
  %call1 = call ptr %notmalloc(i32 %size) #1
  %call2 = call ptr @memset(ptr %call1, i32 0, i32 %size) #1
  ret ptr %call2
}

; This doesn't fire currently because the malloc has more than one use.
; Notice that malloc + memset pattern is now handled by DSE in a more general way.

define ptr @pr25892(i32 %size) #0 {
; CHECK-LABEL: @pr25892(
; CHECK-NEXT:  entry:
; CHECK-NEXT:    [[CALL:%.*]] = tail call ptr @malloc(i32 [[SIZE:%.*]]) #[[ATTR0]]
; CHECK-NEXT:    [[CMP:%.*]] = icmp eq ptr [[CALL]], null
; CHECK-NEXT:    br i1 [[CMP]], label [[CLEANUP:%.*]], label [[IF_END:%.*]]
; CHECK:       if.end:
; CHECK-NEXT:    tail call void @llvm.memset.p0.i32(ptr nonnull align 1 [[CALL]], i8 0, i32 [[SIZE]], i1 false) #[[ATTR0]]
; CHECK-NEXT:    br label [[CLEANUP]]
; CHECK:       cleanup:
; CHECK-NEXT:    [[RETVAL_0:%.*]] = phi ptr [ [[CALL]], [[IF_END]] ], [ null, [[ENTRY:%.*]] ]
; CHECK-NEXT:    ret ptr [[RETVAL_0]]
;
entry:
  %call = tail call ptr @malloc(i32 %size) #1
  %cmp = icmp eq ptr %call, null
  br i1 %cmp, label %cleanup, label %if.end
if.end:
  %call2 = tail call ptr @memset(ptr nonnull %call, i32 0, i32 %size) #1
  br label %cleanup
cleanup:
  %retval.0 = phi ptr [ %call, %if.end ], [ null, %entry ]
  ret ptr %retval.0
}

; If there's a calloc transform, the store must also be eliminated.

define ptr @buffer_is_modified_then_memset(i32 %size) {
; CHECK-LABEL: @buffer_is_modified_then_memset(
; CHECK-NEXT:    [[PTR:%.*]] = tail call ptr @malloc(i32 [[SIZE:%.*]]) #[[ATTR0]]
; CHECK-NEXT:    store i8 1, ptr [[PTR]], align 1
; CHECK-NEXT:    tail call void @llvm.memset.p0.i32(ptr nonnull align 1 [[PTR]], i8 0, i32 [[SIZE]], i1 false) #[[ATTR0]]
; CHECK-NEXT:    ret ptr [[PTR]]
;
  %ptr = tail call ptr @malloc(i32 %size) #1
  store i8 1, ptr %ptr           ;; fdata[0] = 1;
  %memset = tail call ptr @memset(ptr nonnull %ptr, i32 0, i32 %size) #1
  ret ptr %memset
}

define ptr @memset_size_select(i1 %b, ptr %ptr) {
; CHECK-LABEL: @memset_size_select(
; CHECK-NEXT:    [[SIZE:%.*]] = select i1 [[B:%.*]], i32 10, i32 50
; CHECK-NEXT:    tail call void @llvm.memset.p0.i32(ptr noundef nonnull align 1 dereferenceable(10) [[PTR:%.*]], i8 0, i32 [[SIZE]], i1 false) #[[ATTR0]]
; CHECK-NEXT:    ret ptr [[PTR]]
;
  %size = select i1 %b, i32 10, i32 50
  %memset = tail call ptr @memset(ptr nonnull %ptr, i32 0, i32 %size) #1
  ret ptr %memset
}


define ptr @memset_size_select2(i1 %b, ptr %ptr) {
; CHECK-LABEL: @memset_size_select2(
; CHECK-NEXT:    [[SIZE:%.*]] = select i1 [[B:%.*]], i32 10, i32 50
; CHECK-NEXT:    tail call void @llvm.memset.p0.i32(ptr noundef nonnull align 1 dereferenceable(80) [[PTR:%.*]], i8 0, i32 [[SIZE]], i1 false) #[[ATTR0]]
; CHECK-NEXT:    ret ptr [[PTR]]
;
  %size = select i1 %b, i32 10, i32 50
  %memset = tail call ptr @memset(ptr nonnull dereferenceable(80) %ptr, i32 0, i32 %size) #1
  ret ptr %memset
}

define ptr @memset_size_select3(i1 %b, ptr %ptr) {
; CHECK-LABEL: @memset_size_select3(
; CHECK-NEXT:    [[SIZE:%.*]] = select i1 [[B:%.*]], i32 10, i32 50
; CHECK-NEXT:    tail call void @llvm.memset.p0.i32(ptr noundef nonnull align 1 dereferenceable(40) [[PTR:%.*]], i8 0, i32 [[SIZE]], i1 false)
; CHECK-NEXT:    ret ptr [[PTR]]
;
  %size = select i1 %b, i32 10, i32 50
  %memset = tail call ptr @memset(ptr dereferenceable_or_null(40) %ptr, i32 0, i32 %size)
  ret ptr %memset
}

define ptr @memset_size_select4(i1 %b, ptr %ptr) {
; CHECK-LABEL: @memset_size_select4(
; CHECK-NEXT:    [[SIZE:%.*]] = select i1 [[B:%.*]], i32 10, i32 50
; CHECK-NEXT:    tail call void @llvm.memset.p0.i32(ptr noundef nonnull align 1 dereferenceable(40) [[PTR:%.*]], i8 0, i32 [[SIZE]], i1 false) #[[ATTR0]]
; CHECK-NEXT:    ret ptr [[PTR]]
;
  %size = select i1 %b, i32 10, i32 50
  %memset = tail call ptr @memset(ptr nonnull dereferenceable_or_null(40) %ptr, i32 0, i32 %size) #1
  ret ptr %memset
}

define ptr @memset_size_ashr(i1 %b, ptr %ptr, i32 %v) {
; CHECK-LABEL: @memset_size_ashr(
; CHECK-NEXT:    [[SIZE:%.*]] = ashr i32 -2, [[V:%.*]]
; CHECK-NEXT:    tail call void @llvm.memset.p0.i32(ptr noundef nonnull align 1 dereferenceable(1) [[PTR:%.*]], i8 0, i32 [[SIZE]], i1 false) #[[ATTR0]]
; CHECK-NEXT:    ret ptr [[PTR]]
;
  %size = ashr i32 -2, %v
  %memset = tail call ptr @memset(ptr nonnull %ptr, i32 0, i32 %size) #1
  ret ptr %memset
}

define ptr @memset_attrs1(i1 %b, ptr %ptr, i32 %size) {
; CHECK-LABEL: @memset_attrs1(
; CHECK-NEXT:    tail call void @llvm.memset.p0.i32(ptr align 1 dereferenceable_or_null(40) [[PTR:%.*]], i8 0, i32 [[SIZE:%.*]], i1 false) #[[ATTR0]]
; CHECK-NEXT:    ret ptr [[PTR]]
;
  %memset = tail call ptr @memset(ptr dereferenceable_or_null(40) %ptr, i32 0, i32 %size) #1
  ret ptr %memset
}

; be sure to drop nonnull since size is unknown and can be 0
; do not change dereferenceable attribute
define ptr @memset_attrs2(i1 %b, ptr %ptr, i32 %size) {
; CHECK-LABEL: @memset_attrs2(
; CHECK-NEXT:    tail call void @llvm.memset.p0.i32(ptr nonnull align 1 dereferenceable(40) [[PTR:%.*]], i8 0, i32 [[SIZE:%.*]], i1 false) #[[ATTR0]]
; CHECK-NEXT:    ret ptr [[PTR]]
;
  %memset = tail call ptr @memset(ptr nonnull dereferenceable(40) %ptr, i32 0, i32 %size) #1
  ret ptr %memset
}

; size is unknown, just copy attrs, no changes in attrs
define ptr @memset_attrs3(i1 %b, ptr %ptr, i32 %size) {
; CHECK-LABEL: @memset_attrs3(
; CHECK-NEXT:    tail call void @llvm.memset.p0.i32(ptr nonnull align 1 dereferenceable_or_null(40) [[PTR:%.*]], i8 0, i32 [[SIZE:%.*]], i1 false) #[[ATTR0]]
; CHECK-NEXT:    ret ptr [[PTR]]
;
  %memset = tail call ptr @memset(ptr nonnull dereferenceable_or_null(40) %ptr, i32 0, i32 %size) #1
  ret ptr %memset
}

; be sure to drop nonnull since size is unknown and can be 0
define ptr @memset_attrs4(i1 %b, ptr %ptr, i32 %size) {
; CHECK-LABEL: @memset_attrs4(
; CHECK-NEXT:    tail call void @llvm.memset.p0.i32(ptr nonnull align 1 [[PTR:%.*]], i8 0, i32 [[SIZE:%.*]], i1 false) #[[ATTR0]]
; CHECK-NEXT:    ret ptr [[PTR]]
;
  %memset = tail call ptr @memset(ptr nonnull %ptr, i32 0, i32 %size) #1
  ret ptr %memset
}

define ptr @test_no_incompatible_attr(ptr %mem, i32 %val, i32 %size) {
; CHECK-LABEL: @test_no_incompatible_attr(
; CHECK-NEXT:    [[TMP1:%.*]] = trunc i32 [[VAL:%.*]] to i8
; CHECK-NEXT:    call void @llvm.memset.p0.i32(ptr align 1 [[MEM:%.*]], i8 [[TMP1]], i32 [[SIZE:%.*]], i1 false)
; CHECK-NEXT:    ret ptr [[MEM]]
;
  %ret = call dereferenceable(1) ptr @memset(ptr %mem, i32 %val, i32 %size)
  ret ptr %ret
}

attributes #0 = { nounwind ssp uwtable }
attributes #1 = { nounwind }
attributes #2 = { nounwind readnone }