14be3f0e88
Add dexter tests using the optnone attribute in various scenarios. Our users
have found optnone useful when debugging optimised code. We have these tests
downstream (and one upstream already: D89873) and we would like to contribute
them if there is any interest.
The tests are fairly self explanatory. Testing optnone with:
* optnone-fastmath.cpp: floats and -ffast-math,
* optnone-simple-functions: simple functions and integer arithmetic,
* optnone-struct-and-methods: a struct with methods,
* optnone-vectors-and-functions: templates and integer vector arithmetic.
optnone-vectors-and-functions contains two FIXMEs. The first problem is that
lldb seems to struggle with evaluating expressions with the templates used
here (example below). Perhaps this is PR42920?
(lldb) p TypeTraits<int __attribute__((ext_vector_type(4)))>::NumElements
error: <user expression 0>:1:1: no template named 'TypeTraits'
TypeTraits<int __attribute__((ext_vector_type(4)))>::NumElements
^
The second is that while lldb cannot evaluate the following expression, gdb
can, but it reports that the variable has been optimzed away. It does this when
compiling at O0 too. llvm-dwarfdump shows that MysteryNumber does have a
location. I don't know whether the DIE is bad or if both debuggers just don't
support it.
TypeTraits<int __attribute__((ext_vector_type(4)))>::MysteryNumber
DW_TAG_variable
DW_AT_specification (0x0000006b "MysteryNumber")
DW_AT_location (DW_OP_addr 0x601028)
DW_AT_linkage_name ("_ZN10TypeTraitsIDv4_iE13MysteryNumberE")
Reviewed By: rnk
Differential Revision: https://reviews.llvm.org/D97668
-*- rst -*-
This is a collection of tests to check debugging information generated by
compiler. This test suite can be checked out inside clang/test folder. This
will enable 'make test' for clang to pick up these tests.
Some tests (in the 'llgdb-tests' directory) are written with debugger
commands and checks for the intended debugger output in the source file,
using DEBUGGER: and CHECK: as prefixes respectively.
For example::
define i32 @f1(i32 %i) nounwind ssp {
; DEBUGGER: break f1
; DEBUGGER: r
; DEBUGGER: p i
; CHECK: $1 = 42
entry:
}
is a testcase where the debugger is asked to break at function 'f1' and
print value of argument 'i'. The expected value of 'i' is 42 in this case.
Other tests are written for use with the 'Dexter' tool (in the 'dexter-tests'
and 'dexter' directories respectively). These use a domain specific language
in comments to describe the intended debugger experience in a more abstract
way than debugger commands. This allows for testing integration across
multiple debuggers from one input language.
For example::
void __attribute__((noinline, optnone)) bar(int *test) {}
int main() {
int test;
test = 23;
bar(&test); // DexLabel('before_bar')
return test; // DexLabel('after_bar')
}
// DexExpectWatchValue('test', '23', on_line='before_bar')
// DexExpectWatchValue('test', '23', on_line='after_bar')
Labels two lines with the names 'before_bar' and 'after_bar', and records that
the 'test' variable is expected to have the value 23 on both of them.