; ModuleID = 'fizzbuzz.c' ; source_filename = "fizzbuzz.c" ; target datalayout = "e-m:w-i64:64-f80:128-n8:16:32:64-S128" ; target triple = "x86_64-pc-windows-msvc19.21.27702" ; This is not strictly LLVM, as it uses the C library function "printf". ; LLVM does not provide a way to print values, so the alternative would be ; to just load the string into memory, and that would be boring. ; Additional comments have been inserted, as well as changes made from the output produced by clang such as putting more meaningful labels for the jumps $"\01??_C@_09NODAFEIA@FizzBuzz?6?$AA@" = comdat any $"\01??_C@_05KEBFOHOF@Fizz?6?$AA@" = comdat any $"\01??_C@_05JKJENPHA@Buzz?6?$AA@" = comdat any $"\01??_C@_03PMGGPEJJ@?$CFd?6?$AA@" = comdat any ;--- String constant defintions @"\01??_C@_09NODAFEIA@FizzBuzz?6?$AA@" = linkonce_odr unnamed_addr constant [10 x i8] c"FizzBuzz\0A\00", comdat, align 1 @"\01??_C@_05KEBFOHOF@Fizz?6?$AA@" = linkonce_odr unnamed_addr constant [6 x i8] c"Fizz\0A\00", comdat, align 1 @"\01??_C@_05JKJENPHA@Buzz?6?$AA@" = linkonce_odr unnamed_addr constant [6 x i8] c"Buzz\0A\00", comdat, align 1 @"\01??_C@_03PMGGPEJJ@?$CFd?6?$AA@" = linkonce_odr unnamed_addr constant [4 x i8] c"%d\0A\00", comdat, align 1 ;--- The declaration for the external C printf function. declare i32 @printf(i8*, ...) ; Function Attrs: noinline nounwind optnone uwtable define i32 @main() #0 { %1 = alloca i32, align 4 store i32 1, i32* %1, align 4 ;--- It does not seem like this branch can be removed br label %loop ;--- while (i <= 100) loop: %2 = load i32, i32* %1, align 4 %3 = icmp sle i32 %2, 100 br i1 %3, label %divisible_15, label %finished ;--- if (i % 15 == 0) divisible_15: %4 = load i32, i32* %1, align 4 %5 = srem i32 %4, 15 %6 = icmp eq i32 %5, 0 br i1 %6, label %print_fizzbuzz, label %divisible_3 ;--- Print 'FizzBuzz' print_fizzbuzz: %7 = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([10 x i8], [10 x i8]* @"\01??_C@_09NODAFEIA@FizzBuzz?6?$AA@", i32 0, i32 0)) br label %next ;--- if (i % 3 == 0) divisible_3: %8 = load i32, i32* %1, align 4 %9 = srem i32 %8, 3 %10 = icmp eq i32 %9, 0 br i1 %10, label %print_fizz, label %divisible_5 ;--- Print 'Fizz' print_fizz: %11 = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([6 x i8], [6 x i8]* @"\01??_C@_05KEBFOHOF@Fizz?6?$AA@", i32 0, i32 0)) br label %next ;--- if (i % 5 == 0) divisible_5: %12 = load i32, i32* %1, align 4 %13 = srem i32 %12, 5 %14 = icmp eq i32 %13, 0 br i1 %14, label %print_buzz, label %print_number ;--- Print 'Buzz' print_buzz: %15 = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([6 x i8], [6 x i8]* @"\01??_C@_05JKJENPHA@Buzz?6?$AA@", i32 0, i32 0)) br label %next ;--- Print the number print_number: %16 = load i32, i32* %1, align 4 %17 = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([4 x i8], [4 x i8]* @"\01??_C@_03PMGGPEJJ@?$CFd?6?$AA@", i32 0, i32 0), i32 %16) ;--- It does not seem like this branch can be removed br label %next ;--- i = i + 1 next: %18 = load i32, i32* %1, align 4 %19 = add nsw i32 %18, 1 store i32 %19, i32* %1, align 4 br label %loop ;--- exit main finished: ret i32 0 } attributes #0 = { noinline nounwind optnone uwtable "correctly-rounded-divide-sqrt-fp-math"="false" "disable-tail-calls"="false" "less-precise-fpmad"="false" "no-frame-pointer-elim"="false" "no-infs-fp-math"="false" "no-jump-tables"="false" "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" "no-trapping-math"="false" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+fxsr,+mmx,+sse,+sse2,+x87" "unsafe-fp-math"="false" "use-soft-float"="false" } !llvm.module.flags = !{!0, !1} !llvm.ident = !{!2} !0 = !{i32 1, !"wchar_size", i32 2} !1 = !{i32 7, !"PIC Level", i32 2} !2 = !{!"clang version 6.0.1 (tags/RELEASE_601/final)"}