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      1 ; Test lib call simplification of __strcpy_chk calls with various values
      2 ; for src, dst, and slen.
      3 ;
      4 ; RUN: opt < %s -instcombine -S | FileCheck %s
      5 
      6 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"
      7 
      8 @a = common global [60 x i8] zeroinitializer, align 1
      9 @b = common global [60 x i8] zeroinitializer, align 1
     10 @.str = private constant [12 x i8] c"abcdefghijk\00"
     11 
     12 ; Check cases where slen >= strlen (src).
     13 
     14 define void @test_simplify1() {
     15 ; CHECK-LABEL: @test_simplify1(
     16   %dst = getelementptr inbounds [60 x i8]* @a, i32 0, i32 0
     17   %src = getelementptr inbounds [12 x i8]* @.str, i32 0, i32 0
     18 
     19 ; CHECK-NEXT: call void @llvm.memcpy.p0i8.p0i8.i32
     20   call i8* @__strcpy_chk(i8* %dst, i8* %src, i32 60)
     21   ret void
     22 }
     23 
     24 define void @test_simplify2() {
     25 ; CHECK-LABEL: @test_simplify2(
     26   %dst = getelementptr inbounds [60 x i8]* @a, i32 0, i32 0
     27   %src = getelementptr inbounds [12 x i8]* @.str, i32 0, i32 0
     28 
     29 ; CHECK-NEXT: call void @llvm.memcpy.p0i8.p0i8.i32
     30   call i8* @__strcpy_chk(i8* %dst, i8* %src, i32 12)
     31   ret void
     32 }
     33 
     34 define void @test_simplify3() {
     35 ; CHECK-LABEL: @test_simplify3(
     36   %dst = getelementptr inbounds [60 x i8]* @a, i32 0, i32 0
     37   %src = getelementptr inbounds [12 x i8]* @.str, i32 0, i32 0
     38 
     39 ; CHECK-NEXT: call void @llvm.memcpy.p0i8.p0i8.i32
     40   call i8* @__strcpy_chk(i8* %dst, i8* %src, i32 -1)
     41   ret void
     42 }
     43 
     44 ; Check cases where there are no string constants.
     45 
     46 define void @test_simplify4() {
     47 ; CHECK-LABEL: @test_simplify4(
     48   %dst = getelementptr inbounds [60 x i8]* @a, i32 0, i32 0
     49   %src = getelementptr inbounds [60 x i8]* @b, i32 0, i32 0
     50 
     51 ; CHECK-NEXT: call i8* @strcpy
     52   call i8* @__strcpy_chk(i8* %dst, i8* %src, i32 -1)
     53   ret void
     54 }
     55 
     56 ; Check case where the string length is not constant.
     57 
     58 define void @test_simplify5() {
     59 ; CHECK-LABEL: @test_simplify5(
     60   %dst = getelementptr inbounds [60 x i8]* @a, i32 0, i32 0
     61   %src = getelementptr inbounds [12 x i8]* @.str, i32 0, i32 0
     62 
     63 ; CHECK: @__memcpy_chk
     64   %len = call i32 @llvm.objectsize.i32(i8* %dst, i1 false)
     65   call i8* @__strcpy_chk(i8* %dst, i8* %src, i32 %len)
     66   ret void
     67 }
     68 
     69 ; Check case where the source and destination are the same.
     70 
     71 define i8* @test_simplify6() {
     72 ; CHECK-LABEL: @test_simplify6(
     73   %dst = getelementptr inbounds [60 x i8]* @a, i32 0, i32 0
     74 
     75 ; CHECK: getelementptr inbounds ([60 x i8]* @a, i32 0, i32 0)
     76   %len = call i32 @llvm.objectsize.i32(i8* %dst, i1 false)
     77   %ret = call i8* @__strcpy_chk(i8* %dst, i8* %dst, i32 %len)
     78   ret i8* %ret
     79 }
     80 
     81 ; Check case where slen < strlen (src).
     82 
     83 define void @test_no_simplify1() {
     84 ; CHECK-LABEL: @test_no_simplify1(
     85   %dst = getelementptr inbounds [60 x i8]* @a, i32 0, i32 0
     86   %src = getelementptr inbounds [60 x i8]* @b, i32 0, i32 0
     87 
     88 ; CHECK-NEXT: call i8* @__strcpy_chk
     89   call i8* @__strcpy_chk(i8* %dst, i8* %src, i32 8)
     90   ret void
     91 }
     92 
     93 declare i8* @__strcpy_chk(i8*, i8*, i32) nounwind
     94 declare i32 @llvm.objectsize.i32(i8*, i1) nounwind readonly
     95