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path: root/llvm/test/Analysis/BasicAA/gep-implicit-trunc-32-bit-pointers.ll
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; RUN: opt -aa-pipeline=basic-aa -passes=aa-eval -print-all-alias-modref-info -disable-output %s 2>&1 | FileCheck %s

target datalayout = "p:32:32:32"

; Test cases with i64 bit GEP indices that will get truncated implicitly to 32
; bit due to the datalayout.

declare void @llvm.assume(i1)

define void @mustalias_overflow_in_32_bit_constants(ptr %ptr) {
; CHECK-LABEL: Function: mustalias_overflow_in_32_bit_constants: 2 pointers, 0 call sites
; CHECK-NEXT:    MustAlias: i8* %gep.1, i8* %ptr
;
  load i8, ptr %ptr
  %gep.1 = getelementptr i8, ptr %ptr, i64 4294967296
  store i8 0, ptr %gep.1
  ret void
}

define void @mustalias_overflow_in_32_with_var_index(ptr %ptr, i64 %n) {
; CHECK-LABEL: Function: mustalias_overflow_in_32_with_var_index
; CHECK:       MustAlias: i8* %gep.1, i8* %gep.2
;
  load [1 x i8], ptr %ptr
  %gep.1 = getelementptr [1 x i8], ptr %ptr, i64 %n, i64 4294967296
  store i8 0, ptr %gep.1
  %gep.2 = getelementptr [1 x i8], ptr %ptr, i64 %n, i64 0
  store i8 1, ptr %gep.2
  ret void
}

define void @noalias_overflow_in_32_bit_constants(ptr %ptr) {
; CHECK-LABEL: Function: noalias_overflow_in_32_bit_constants: 3 pointers, 0 call sites
; CHECK-NEXT:    MustAlias: i8* %gep.1, i8* %ptr
; CHECK-NEXT:    NoAlias:  i8* %gep.2, i8* %ptr
; CHECK-NEXT:    NoAlias:  i8* %gep.1, i8* %gep.2
;
  load i8, ptr %ptr
  %gep.1 = getelementptr i8, ptr %ptr, i64 4294967296
  store i8 0, ptr %gep.1
  %gep.2 = getelementptr i8, ptr %ptr, i64 1
  store i8 1, ptr %gep.2
  ret void
}

; The GEP indices get implicitly truncated to 32 bit, so multiples of 2^32
; (=4294967296) will be 0.
; See https://alive2.llvm.org/ce/z/HHjQgb.
define void @mustalias_overflow_in_32_bit_add_mul_gep(ptr %ptr, i64 %i) {
; CHECK-LABEL: Function: mustalias_overflow_in_32_bit_add_mul_gep: 3 pointers, 1 call sites
; CHECK-NEXT:    MayAlias: i8* %gep.1, i8* %ptr
; CHECK-NEXT:    MayAlias: i8* %gep.2, i8* %ptr
; CHECK-NEXT:    MayAlias: i8* %gep.1, i8* %gep.2
;
  load i8, ptr %ptr
  %s.1 = icmp sgt i64 %i, 0
  call void @llvm.assume(i1 %s.1)

  %mul = mul nuw nsw i64 %i, 4294967296
  %add = add nuw nsw i64 %mul, %i
  %gep.1 = getelementptr i8, ptr %ptr, i64 %add
  store i8 0, ptr %gep.1
  %gep.2 = getelementptr i8, ptr %ptr, i64 %i
  store i8 1, ptr %gep.2
  ret void
}

define void @mayalias_overflow_in_32_bit_non_zero(ptr %ptr, i64 %n) {
; CHECK-LABEL: Function: mayalias_overflow_in_32_bit_non_zero
; CHECK:    MayAlias: i8* %gep, i8* %ptr
;
  load i8, ptr %ptr
  %c = icmp ne i64 %n, 0
  call void @llvm.assume(i1 %c)
  store i8 0, ptr %ptr
  %gep = getelementptr i8, ptr %ptr, i64 %n
  store i8 1, ptr %gep
  ret void
}

define void @mayalias_overflow_in_32_bit_positive(ptr %ptr, i64 %n) {
; CHECK-LABEL: Function: mayalias_overflow_in_32_bit_positive
; CHECK:    NoAlias: i8* %gep.1, i8* %ptr
; CHECK:    MayAlias: i8* %gep.2, i8* %ptr
; CHECK:    MayAlias: i8* %gep.1, i8* %gep.2
;
  load i8, ptr %ptr
  %c = icmp sgt i64 %n, 0
  call void @llvm.assume(i1 %c)
  %gep.1 = getelementptr i8, ptr %ptr, i64 -1
  store i8 0, ptr %gep.1
  %gep.2 = getelementptr i8, ptr %ptr, i64 %n
  store i8 1, ptr %gep.2
  ret void
}