I wonder if it is possible to make the LLVM opt tool to report in detail which optimization passes are successfully used during each optimization level like -O1,-O2, etc.
For example, here is the naive bitcode of the file foo.bc:
define dso_local i32 @main() #0 {
%1 = alloca i32, align 4
%2 = alloca i32, align 4
%3 = alloca i32, align 4
store i32 0, i32* %1, align 4
store i32 1, i32* %2, align 4
store i32 1, i32* %3, align 4
%4 = load i32, i32* %2, align 4
ret i32 %4
}
And here is the bitcode obtained after running opt -O1 foo.bc -o foo.opt.bc
; Function Attrs: noinline norecurse nounwind readnone uwtable
define dso_local i32 @main() local_unnamed_addr #0 {
ret i32 1
}
How can I obtain information about passes applied by LLVM opt in the above optimization?
I tried to use several flags of opt of LLVM 10.0, such as --pass-remarks-filter, --debugify-each, --verify-each, --lto-pass-remarks-filter, etc but none of them work.
Does anyone know how to get such kind of information?
