Dear Developers,
I would like get detailed info if verification of the intermediate representation fails.
Currently I am using IRBuilder to create a module, and I encountered an error, which I cannot trace back to the IRBuilder related call, which caused the error:
“Instruction does not dominate all uses!
%14 = load i32, i32* @r6
%11 = trunc i32 %14 to i8
LLVM ERROR: Broken function found, compilation aborted!”
This description is too losely specified for me to know, where the causing code is located. Getting 20 lines instead of 2 would help. Getting additional info of the broken function could also help. How can this be solved?
Best regards,
Norbert Dajka
Hi Norbert,
Currently I am using IRBuilder to create a module, and I encountered an error, which I cannot trace back to the IRBuilder related call, which caused the error:
"Instruction does not dominate all uses!
%14 = load i32, i32* @r6
%11 = trunc i32 %14 to i8
LLVM ERROR: Broken function found, compilation aborted!"
This description is too losely specified for me to know, where the causing code is located. Getting 20 lines instead of 2 would help. Getting additional info of the broken function could also help. How can this be solved?
This looks like an error in the Verifier. I often find them a bit
terse too, but I don't think there's a command-line option to
automatically be more verbose on an error. I tend to set a breakpoint
in "CheckFailed" and go up a few stack levels. That usually lets you
dump the function or module that's causing problems.
Alternatively, you might dump your functions just after creating them
and look for truncs & loads with those operands.
Cheers.
Tim.
One problem I see with the IR verifier’s output is that it does not display the functon(s) in which the error occurs.
A common error on my part is to reference a value generated in one function, from a different function. (This may seem strange, but it can happen because I cache the LLVM value of evaluating an expression in some required circumstances, and I need to explicitly purge this cached value if I know that I need to evaluate an expression in two different contexts.) When this happens I need to grep the IR to try to figure out which functions are involved.