Closed
Description
OS and Platform:
Ubuntu 20.04.4 LTS
clang version 17.0.4
Target: x86_64-unknown-linux-gnu
Thread model: posix
InstalledDir: /home/cuisk/ctc/llvm-releases/llvm-17.0.4/build/bin
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/8
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/9
Selected GCC installation: /usr/lib/gcc/x86_64-linux-gnu/9
Candidate multilib: .;@m64
Candidate multilib: 32;@m32
Candidate multilib: x32;@MX32
Selected multilib: .;@m64
Command Lines:
opt -passes=globalopt,bdce,flattencfg b.ll -o a.opt.bc
clang a.opt.bc -o a.out
./a.out
2
opt b.ll -o a0.opt.bc
clang a0.opt.bc -o a0.out
./a0.out
1Source Code:
; ModuleID = 'a.c'
source_filename = "a.c"
target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-unknown-linux-gnu"
@.str = private unnamed_addr constant [4 x i8] c"%d\0A\00", align 1
@a = dso_local global i32 0, align 4
@c = dso_local global i32 0, align 4
@b = internal global i16 0, align 2
; Function Attrs: nounwind uwtable
define dso_local i32 @main() #0 {
%1 = call i32 @e()
%2 = load i32, ptr @a, align 4, !tbaa !5
%3 = call i32 (ptr, ...) @printf(ptr noundef @.str, i32 noundef %2)
ret i32 0
}
declare i32 @printf(ptr noundef, ...) #1
; Function Attrs: nounwind uwtable
define internal i32 @e() #0 {
%1 = alloca i32, align 4
%2 = alloca i16, align 2
call void @llvm.lifetime.start.p0(i64 2, ptr %2) #3
store i16 4, ptr %2, align 2, !tbaa !9
%3 = load i16, ptr %2, align 2, !tbaa !9
%4 = zext i16 %3 to i32
%5 = call i32 @d(i8 noundef signext 0, i32 noundef %4)
call void @llvm.lifetime.end.p0(i64 2, ptr %2) #3
%6 = load i32, ptr %1, align 4
ret i32 %6
}
; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture) #2
; Function Attrs: nounwind uwtable
define internal i32 @d(i8 noundef signext %0, i32 noundef %1) #0 {
%3 = alloca i32, align 4
%4 = alloca i8, align 1
%5 = alloca i32, align 4
%6 = alloca i32, align 4
store i8 %0, ptr %4, align 1, !tbaa !11
store i32 %1, ptr %5, align 4, !tbaa !5
call void @llvm.lifetime.start.p0(i64 4, ptr %6) #3
store i32 0, ptr %6, align 4, !tbaa !5
%7 = load i16, ptr @b, align 2, !tbaa !9
%8 = zext i16 %7 to i32
%9 = load i32, ptr %5, align 4, !tbaa !5
%10 = and i32 %9, 0
%11 = icmp ne i32 %10, 0
br i1 %11, label %13, label %12
12: ; preds = %2
br label %13
13: ; preds = %12, %2
%14 = phi i1 [ true, %2 ], [ true, %12 ]
%15 = zext i1 %14 to i32
%16 = and i32 %8, %15
%17 = icmp ne i32 %16, 0
br i1 %17, label %18, label %19
18: ; preds = %13
br label %19
19: ; preds = %18, %13
%20 = phi i1 [ false, %13 ], [ true, %18 ]
%21 = zext i1 %20 to i32
%22 = trunc i32 %21 to i16
%23 = call signext i16 @safe_add_func_int16_t_s_s(i16 noundef signext %22, i16 noundef signext 1)
%24 = load i32, ptr @c, align 4, !tbaa !5
%25 = trunc i32 %24 to i16
%26 = call signext i16 @safe_add_func_int16_t_s_s(i16 noundef signext %23, i16 noundef signext %25)
%27 = load i32, ptr %6, align 4, !tbaa !5
%28 = call zeroext i16 @safe_rshift_func_uint16_t_u_u(i16 noundef zeroext %26, i32 noundef %27)
%29 = zext i16 %28 to i32
store i32 %29, ptr @a, align 4, !tbaa !5
call void @llvm.lifetime.end.p0(i64 4, ptr %6) #3
%30 = load i32, ptr %3, align 4
ret i32 %30
}
; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture) #2
; Function Attrs: nounwind uwtable
define internal zeroext i16 @safe_rshift_func_uint16_t_u_u(i16 noundef zeroext %0, i32 noundef %1) #0 {
%3 = alloca i16, align 2
%4 = alloca i32, align 4
store i16 %0, ptr %3, align 2, !tbaa !9
store i32 %1, ptr %4, align 4, !tbaa !5
%5 = load i32, ptr %4, align 4, !tbaa !5
%6 = icmp uge i32 %5, 32
br i1 %6, label %7, label %10
7: ; preds = %2
%8 = load i16, ptr %3, align 2, !tbaa !9
%9 = zext i16 %8 to i32
br label %15
10: ; preds = %2
%11 = load i16, ptr %3, align 2, !tbaa !9
%12 = zext i16 %11 to i32
%13 = load i32, ptr %4, align 4, !tbaa !5
%14 = ashr i32 %12, %13
br label %15
15: ; preds = %10, %7
%16 = phi i32 [ %9, %7 ], [ %14, %10 ]
%17 = trunc i32 %16 to i16
ret i16 %17
}
; Function Attrs: nounwind uwtable
define internal signext i16 @safe_add_func_int16_t_s_s(i16 noundef signext %0, i16 noundef signext %1) #0 {
%3 = alloca i16, align 2
%4 = alloca i16, align 2
store i16 %0, ptr %3, align 2, !tbaa !9
store i16 %1, ptr %4, align 2, !tbaa !9
%5 = load i16, ptr %3, align 2, !tbaa !9
%6 = sext i16 %5 to i32
%7 = load i16, ptr %4, align 2, !tbaa !9
%8 = sext i16 %7 to i32
%9 = add nsw i32 %6, %8
%10 = trunc i32 %9 to i16
ret i16 %10
}
attributes #0 = { nounwind uwtable "min-legal-vector-width"="0" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cmov,+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" }
attributes #1 = { "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cmov,+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" }
attributes #2 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #3 = { nounwind }
!llvm.module.flags = !{!0, !1, !2, !3}
!llvm.ident = !{!4}
!0 = !{i32 1, !"wchar_size", i32 4}
!1 = !{i32 8, !"PIC Level", i32 2}
!2 = !{i32 7, !"PIE Level", i32 2}
!3 = !{i32 7, !"uwtable", i32 2}
!4 = !{!"clang version 17.0.4"}
!5 = !{!6, !6, i64 0}
!6 = !{!"int", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C/C++ TBAA"}
!9 = !{!10, !10, i64 0}
!10 = !{!"short", !7, i64 0}
!11 = !{!7, !7, i64 0}