[LLVMdev] Forcing function inline not working

[madiyaan]

Thanks for your message. However, even with using version 2.5 of llvm the
function is not inlined. Can you try this with your llvm with the same opt
flags, which are as follows?

-O3 -debug-only=inline -mem2reg

If it does work for you, can you tell me the exact flags you used for clang
or llvm-gcc to produce the .bc file and the exact flags you specified when
you invoked opt?

Does the inlining happen at clang level or after opt?


Dale Johannesen wrote:
> 
> 
> On Sep 16, 2009, at 6:55 PM, madiyaan wrote:
> 
>>
>> I have the following code:
>>
>> static inline void foo() __attribute((always_inline));
>>
>> int a;
>> static inline void foo()
>> {
>>  a++;
>> }
>>
>> int main(int argc, char *argv[])
>> {
>>  foo();
>>  return 0;
>> }
> 
> This works fine in current sources.  You should upgrade; 2.5 has been  
> out for a while and 2.6 will be soon.
> 
>> However, the code generated by llvm 2.4 toolchain does not inline this
>> function. opt retains the function call. Here is the output when I  
>> try to
>> compile with -debug-only=inline:
>>
>> ..\..\..\win32\bin\win32\debug\opt.exe -O3 -debug-only=inline - 
>> mem2reg -f -o
>> test_opt.bc test.bc
>> Inliner visiting SCC: foo: 0 call sites.
>> Inliner visiting SCC: main: 1 call sites.
>>    Inlining: cost=always, Call:        call void (...)* @foo()
>> Inliner visiting SCC: INDIRECTNODE: 0 call sites.
>>
>> Here is the .ll file:
>>
>> ; ModuleID = 'test_opt.bc'
>> 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-f80:32:32"
>> target triple = "i386-pc-win32"
>> @a = common global i32 0, align 4		; <i32*> [#uses=2]
>>
>> define i32 @main(i32 %argc, i8** %argv) nounwind {
>> entry:
>> 	tail call void (...)* @foo()
>> 	ret i32 0
>> }
>>
>> define internal void @foo(...) nounwind alwaysinline {
>> entry:
>> 	%tmp = load i32* @a		; <i32> [#uses=1]
>> 	%inc = add i32 %tmp, 1		; <i32> [#uses=1]
>> 	store i32 %inc, i32* @a
>> 	ret void
>> }
>>
>>
>> What am I doing wrong here? Is there a way to force a function to be  
>> inlined
>> by opt?
>>
>> Best Regards,
>> -- 
>> View this message in context:
>> http://www.nabble.com/Forcing-function-inline-not-working-tp25483934p25483934.html
>> Sent from the LLVM - Dev mailing list archive at Nabble.com.
>>
>> _______________________________________________
>> LLVM Developers mailing list
>> LLVMdev at cs.uiuc.edu         http://llvm.cs.uiuc.edu
>> http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev
> 
> _______________________________________________
> LLVM Developers mailing list
> LLVMdev at cs.uiuc.edu         http://llvm.cs.uiuc.edu
> http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev
> 
> 

-- 
View this message in context: http://www.nabble.com/Forcing-function-inline-not-working-tp25483934p25491988.html
Sent from the LLVM - Dev mailing list archive at Nabble.com.