[llvm-dev] How to generate a .ll file with functions' parameter names

[Hideto Ueno via llvm-dev]

Hi Alberto,

Variable names in LLVM IR are meaningless and only used for debugging.
However, if you want to preserve the variable name, you can use
`-fno-discard-value-names` option.

Regards,
Hideto

2019年12月8日(日) 17:38 Alberto Barbaro via llvm-dev <llvm-dev at lists.llvm.org>:

> Hi all,
> I'm trying to obtain a .ll with parameters name for every function. My
> simple c C is the following:
>
> int sum(int a, int b) {
> return a+b;
> }
>
> int main() {
> sum(1,2);
> }
>
> I obtain the .ll with the following commands:
>
> clang -emit-llvm sum.c -c
> llvm-dis-7 sum.bc
>
> The obtained .ll is:
>
> cat sum.ll
> ; ModuleID = 'sum.bc'
> source_filename = "sum.c"
> target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
> target triple = "x86_64-pc-linux-gnu"
>
> ; Function Attrs: noinline nounwind optnone uwtable
> define i32 @sum(i32, i32) #0 {
>   %3 = alloca i32, align 4
>   %4 = alloca i32, align 4
>   store i32 %0, i32* %3, align 4
>   store i32 %1, i32* %4, align 4
>   %5 = load i32, i32* %3, align 4
>   %6 = load i32, i32* %4, align 4
>   %7 = add nsw i32 %5, %6
>   ret i32 %7
> }
>
> ; Function Attrs: noinline nounwind optnone uwtable
> define i32 @main() #0 {
>   %1 = call i32 @sum(i32 1, i32 2)
>   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"="true" "no-frame-pointer-elim-non-leaf"
> "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}
> !llvm.ident = !{!1}
>
> !0 = !{i32 1, !"wchar_size", i32 4}
> !1 = !{!"clang version 6.0.1-svn334776-1~exp1~20190309042703.125
> (branches/release_60)"}
>
> Could you tell me why I don't see a and b parameters for the sum function?
>
> Thanks
> Alberto
> _______________________________________________
> LLVM Developers mailing list
> llvm-dev at lists.llvm.org
> https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20191208/aaa3f726/attachment.html>