diff options
Diffstat (limited to 'docs/CommandGuide')
| -rw-r--r-- | docs/CommandGuide/FileCheck.rst | 49 | ||||
| -rw-r--r-- | docs/CommandGuide/lit.rst | 4 |
2 files changed, 51 insertions, 2 deletions
diff --git a/docs/CommandGuide/FileCheck.rst b/docs/CommandGuide/FileCheck.rst index fce63ba..0d98349 100644 --- a/docs/CommandGuide/FileCheck.rst +++ b/docs/CommandGuide/FileCheck.rst @@ -194,6 +194,55 @@ can be used: ; CHECK: ret i8 } +The "CHECK-DAG:" directive +~~~~~~~~~~~~~~~~~~~~~~~~~~ + +If it's necessary to match strings that don't occur in a strictly sequential +order, "``CHECK-DAG:``" could be used to verify them between two matches (or +before the first match, or after the last match). For example, clang emits +vtable globals in reverse order. Using ``CHECK-DAG:``, we can keep the checks +in the natural order: + +.. code-block:: c++ + + // RUN: %clang_cc1 %s -emit-llvm -o - | FileCheck %s + + struct Foo { virtual void method(); }; + Foo f; // emit vtable + // CHECK-DAG: @_ZTV3Foo = + + struct Bar { virtual void method(); }; + Bar b; + // CHECK-DAG: @_ZTV3Bar = + + +With captured variables, ``CHECK-DAG:`` is able to match valid topological +orderings of a DAG with edges from the definition of a variable to its use. +It's useful, e.g., when your test cases need to match different output +sequences from the instruction scheduler. For example, + +.. code-block:: llvm + + ; CHECK-DAG: add [[REG1:r[0-9]+]], r1, r2 + ; CHECK-DAG: add [[REG2:r[0-9]+]], r3, r4 + ; CHECK: mul r5, [[REG1]], [[REG2]] + +In this case, any order of that two ``add`` instructions will be allowed. + +``CHECK-NOT:`` directives could be mixed with ``CHECK-DAG:`` directives to +exclude strings between the surrounding ``CHECK-DAG:`` directives. As a result, +the surrounding ``CHECK-DAG:`` directives cannot be reordered, i.e. all +occurrences matching ``CHECK-DAG:`` before ``CHECK-NOT:`` must not fall behind +occurrences matching ``CHECK-DAG:`` after ``CHECK-NOT:``. For example, + +.. code-block:: llvm + + ; CHECK-DAG: BEFORE + ; CHECK-NOT: NOT + ; CHECK-DAG: AFTER + +This case will reject input strings where ``BEFORE`` occurs after ``AFTER``. + FileCheck Pattern Matching Syntax ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ diff --git a/docs/CommandGuide/lit.rst b/docs/CommandGuide/lit.rst index 40c7646..2f6d9a1 100644 --- a/docs/CommandGuide/lit.rst +++ b/docs/CommandGuide/lit.rst @@ -283,7 +283,7 @@ executed, two important global variables are predefined: discover and run tests in the test suite. Generally this will be a builtin test format available from the *lit.formats* module. - **test_src_root** The filesystem path to the test suite root. For out-of-dir + **test_source_root** The filesystem path to the test suite root. For out-of-dir builds this is the directory that will be scanned for tests. **test_exec_root** For out-of-dir builds, the path to the test suite root inside @@ -320,7 +320,7 @@ TEST DISCOVERY ~~~~~~~~~~~~~~ Once test suites are located, :program:`lit` recursively traverses the source -directory (following *test_src_root*) looking for tests. When :program:`lit` +directory (following *test_source_root*) looking for tests. When :program:`lit` enters a sub-directory, it first checks to see if a nested test suite is defined in that directory. If so, it loads that test suite recursively, otherwise it instantiates a local test config for the directory (see |