| ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py |
| ; Test that the strlen library call simplifier works correctly. |
| ; |
| ; RUN: opt < %s -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" |
| |
| @hello = constant [6 x i8] c"hello\00" |
| @longer = constant [7 x i8] c"longer\00" |
| @null = constant [1 x i8] zeroinitializer |
| @null_hello = constant [7 x i8] c"\00hello\00" |
| @nullstring = constant i8 0 |
| @a = common global [32 x i8] zeroinitializer, align 1 |
| @null_hello_mid = constant [13 x i8] c"hello wor\00ld\00" |
| |
| declare i32 @strlen(i8*) |
| |
| ; Check strlen(string constant) -> integer constant. |
| |
| define i32 @test_simplify1() { |
| ; CHECK-LABEL: @test_simplify1( |
| ; CHECK-NEXT: ret i32 5 |
| ; |
| %hello_p = getelementptr [6 x i8], [6 x i8]* @hello, i32 0, i32 0 |
| %hello_l = call i32 @strlen(i8* %hello_p) |
| ret i32 %hello_l |
| } |
| |
| define i32 @test_simplify2() { |
| ; CHECK-LABEL: @test_simplify2( |
| ; CHECK-NEXT: ret i32 0 |
| ; |
| %null_p = getelementptr [1 x i8], [1 x i8]* @null, i32 0, i32 0 |
| %null_l = call i32 @strlen(i8* %null_p) |
| ret i32 %null_l |
| } |
| |
| define i32 @test_simplify3() { |
| ; CHECK-LABEL: @test_simplify3( |
| ; CHECK-NEXT: ret i32 0 |
| ; |
| %null_hello_p = getelementptr [7 x i8], [7 x i8]* @null_hello, i32 0, i32 0 |
| %null_hello_l = call i32 @strlen(i8* %null_hello_p) |
| ret i32 %null_hello_l |
| } |
| |
| define i32 @test_simplify4() { |
| ; CHECK-LABEL: @test_simplify4( |
| ; CHECK-NEXT: ret i32 0 |
| ; |
| %len = tail call i32 @strlen(i8* @nullstring) nounwind |
| ret i32 %len |
| } |
| |
| ; Check strlen(x) == 0 --> *x == 0. |
| |
| define i1 @test_simplify5() { |
| ; CHECK-LABEL: @test_simplify5( |
| ; CHECK-NEXT: ret i1 false |
| ; |
| %hello_p = getelementptr [6 x i8], [6 x i8]* @hello, i32 0, i32 0 |
| %hello_l = call i32 @strlen(i8* %hello_p) |
| %eq_hello = icmp eq i32 %hello_l, 0 |
| ret i1 %eq_hello |
| } |
| |
| define i1 @test_simplify6(i8* %str_p) { |
| ; CHECK-LABEL: @test_simplify6( |
| ; CHECK-NEXT: [[STRLENFIRST:%.*]] = load i8, i8* [[STR_P:%.*]], align 1 |
| ; CHECK-NEXT: [[EQ_NULL:%.*]] = icmp eq i8 [[STRLENFIRST]], 0 |
| ; CHECK-NEXT: ret i1 [[EQ_NULL]] |
| ; |
| %str_l = call i32 @strlen(i8* %str_p) |
| %eq_null = icmp eq i32 %str_l, 0 |
| ret i1 %eq_null |
| } |
| |
| ; Check strlen(x) != 0 --> *x != 0. |
| |
| define i1 @test_simplify7() { |
| ; CHECK-LABEL: @test_simplify7( |
| ; CHECK-NEXT: ret i1 true |
| ; |
| %hello_p = getelementptr [6 x i8], [6 x i8]* @hello, i32 0, i32 0 |
| %hello_l = call i32 @strlen(i8* %hello_p) |
| %ne_hello = icmp ne i32 %hello_l, 0 |
| ret i1 %ne_hello |
| } |
| |
| define i1 @test_simplify8(i8* %str_p) { |
| ; CHECK-LABEL: @test_simplify8( |
| ; CHECK-NEXT: [[STRLENFIRST:%.*]] = load i8, i8* [[STR_P:%.*]], align 1 |
| ; CHECK-NEXT: [[NE_NULL:%.*]] = icmp ne i8 [[STRLENFIRST]], 0 |
| ; CHECK-NEXT: ret i1 [[NE_NULL]] |
| ; |
| %str_l = call i32 @strlen(i8* %str_p) |
| %ne_null = icmp ne i32 %str_l, 0 |
| ret i1 %ne_null |
| } |
| |
| define i32 @test_simplify9(i1 %x) { |
| ; CHECK-LABEL: @test_simplify9( |
| ; CHECK-NEXT: [[TMP1:%.*]] = select i1 %x, i32 5, i32 6 |
| ; CHECK-NEXT: ret i32 [[TMP1]] |
| ; |
| %hello = getelementptr [6 x i8], [6 x i8]* @hello, i32 0, i32 0 |
| %longer = getelementptr [7 x i8], [7 x i8]* @longer, i32 0, i32 0 |
| %s = select i1 %x, i8* %hello, i8* %longer |
| %l = call i32 @strlen(i8* %s) |
| ret i32 %l |
| } |
| |
| ; Check the case that should be simplified to a sub instruction. |
| ; strlen(@hello + x) --> 5 - x |
| |
| define i32 @test_simplify10(i32 %x) { |
| ; CHECK-LABEL: @test_simplify10( |
| ; CHECK-NEXT: [[TMP1:%.*]] = sub i32 5, %x |
| ; CHECK-NEXT: ret i32 [[TMP1]] |
| ; |
| %hello_p = getelementptr inbounds [6 x i8], [6 x i8]* @hello, i32 0, i32 %x |
| %hello_l = call i32 @strlen(i8* %hello_p) |
| ret i32 %hello_l |
| } |
| |
| ; strlen(@null_hello_mid + (x & 7)) --> 9 - (x & 7) |
| |
| define i32 @test_simplify11(i32 %x) { |
| ; CHECK-LABEL: @test_simplify11( |
| ; CHECK-NEXT: [[AND:%.*]] = and i32 %x, 7 |
| ; CHECK-NEXT: [[TMP1:%.*]] = sub nsw i32 9, [[AND]] |
| ; CHECK-NEXT: ret i32 [[TMP1]] |
| ; |
| %and = and i32 %x, 7 |
| %hello_p = getelementptr inbounds [13 x i8], [13 x i8]* @null_hello_mid, i32 0, i32 %and |
| %hello_l = call i32 @strlen(i8* %hello_p) |
| ret i32 %hello_l |
| } |
| |
| ; Check cases that shouldn't be simplified. |
| |
| define i32 @test_no_simplify1() { |
| ; CHECK-LABEL: @test_no_simplify1( |
| ; CHECK-NEXT: [[A_L:%.*]] = call i32 @strlen(i8* getelementptr inbounds ([32 x i8], [32 x i8]* @a, i32 0, i32 0)) |
| ; CHECK-NEXT: ret i32 [[A_L]] |
| ; |
| %a_p = getelementptr [32 x i8], [32 x i8]* @a, i32 0, i32 0 |
| %a_l = call i32 @strlen(i8* %a_p) |
| ret i32 %a_l |
| } |
| |
| ; strlen(@null_hello + x) should not be simplified to a sub instruction. |
| |
| define i32 @test_no_simplify2(i32 %x) { |
| ; CHECK-LABEL: @test_no_simplify2( |
| ; CHECK-NEXT: [[HELLO_P:%.*]] = getelementptr inbounds [7 x i8], [7 x i8]* @null_hello, i32 0, i32 %x |
| ; CHECK-NEXT: [[HELLO_L:%.*]] = call i32 @strlen(i8* nonnull [[HELLO_P]]) |
| ; CHECK-NEXT: ret i32 [[HELLO_L]] |
| ; |
| %hello_p = getelementptr inbounds [7 x i8], [7 x i8]* @null_hello, i32 0, i32 %x |
| %hello_l = call i32 @strlen(i8* %hello_p) |
| ret i32 %hello_l |
| } |
| |
| define i32 @test_no_simplify2_no_null_opt(i32 %x) #0 { |
| ; CHECK-LABEL: @test_no_simplify2_no_null_opt( |
| ; CHECK-NEXT: [[HELLO_P:%.*]] = getelementptr inbounds [7 x i8], [7 x i8]* @null_hello, i32 0, i32 %x |
| ; CHECK-NEXT: [[HELLO_L:%.*]] = call i32 @strlen(i8* [[HELLO_P]]) |
| ; CHECK-NEXT: ret i32 [[HELLO_L]] |
| ; |
| %hello_p = getelementptr inbounds [7 x i8], [7 x i8]* @null_hello, i32 0, i32 %x |
| %hello_l = call i32 @strlen(i8* %hello_p) |
| ret i32 %hello_l |
| } |
| |
| ; strlen(@null_hello_mid + (x & 15)) should not be simplified to a sub instruction. |
| |
| define i32 @test_no_simplify3(i32 %x) { |
| ; CHECK-LABEL: @test_no_simplify3( |
| ; CHECK-NEXT: [[AND:%.*]] = and i32 %x, 15 |
| ; CHECK-NEXT: [[HELLO_P:%.*]] = getelementptr inbounds [13 x i8], [13 x i8]* @null_hello_mid, i32 0, i32 [[AND]] |
| ; CHECK-NEXT: [[HELLO_L:%.*]] = call i32 @strlen(i8* nonnull [[HELLO_P]]) |
| ; CHECK-NEXT: ret i32 [[HELLO_L]] |
| ; |
| %and = and i32 %x, 15 |
| %hello_p = getelementptr inbounds [13 x i8], [13 x i8]* @null_hello_mid, i32 0, i32 %and |
| %hello_l = call i32 @strlen(i8* %hello_p) |
| ret i32 %hello_l |
| } |
| |
| define i32 @test_no_simplify3_on_null_opt(i32 %x) #0 { |
| ; CHECK-LABEL: @test_no_simplify3_on_null_opt( |
| ; CHECK-NEXT: [[AND:%.*]] = and i32 %x, 15 |
| ; CHECK-NEXT: [[HELLO_P:%.*]] = getelementptr inbounds [13 x i8], [13 x i8]* @null_hello_mid, i32 0, i32 [[AND]] |
| ; CHECK-NEXT: [[HELLO_L:%.*]] = call i32 @strlen(i8* [[HELLO_P]]) |
| ; CHECK-NEXT: ret i32 [[HELLO_L]] |
| ; |
| %and = and i32 %x, 15 |
| %hello_p = getelementptr inbounds [13 x i8], [13 x i8]* @null_hello_mid, i32 0, i32 %and |
| %hello_l = call i32 @strlen(i8* %hello_p) |
| ret i32 %hello_l |
| } |
| |
| attributes #0 = { "null-pointer-is-valid"="true" } |
