From bbb2a7a2cf43eca2870a7063404930866136716f Mon Sep 17 00:00:00 2001 From: Reid Spencer Date: Sat, 14 Apr 2007 21:46:15 +0000 Subject: [PATCH] For PR1319: Rewrite much of the DejaGnu section to bring it in line with the new facilities in llvm.exp. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@36015 91177308-0d34-0410-b5e6-96231b3b80d8 --- docs/TestingGuide.html | 248 ++++++++++++++++++++++++++++++----------- 1 file changed, 183 insertions(+), 65 deletions(-) diff --git a/docs/TestingGuide.html b/docs/TestingGuide.html index 409223184b4..584b632e04c 100644 --- a/docs/TestingGuide.html +++ b/docs/TestingGuide.html @@ -275,81 +275,199 @@ location of these external programs is configured by the llvm-test
DejaGNU Structure
-
-

The LLVM test suite is partially driven by DejaGNU and partially -driven by GNU Make. Specifically, the Features and Regression tests -are all driven by DejaGNU. The llvm-test -module is currently driven by a set of Makefiles.

+

The LLVM test suite is partially driven by DejaGNU and partially driven by + GNU Make. Specifically, the Features and Regression tests are all driven by + DejaGNU. The llvm-test module is currently driven by a set of + Makefiles.

-

The DejaGNU structure is very simple, but does require some -information to be set. This information is gathered via configure and -is written to a file, site.exp in llvm/test. The -llvm/test -Makefile does this work for you.

+

The DejaGNU structure is very simple, but does require some information to + be set. This information is gathered via configure and is written + to a file, site.exp in llvm/test. The llvm/test + Makefile does this work for you.

-

In order for DejaGNU to work, each directory of tests must have a -dg.exp file. This file is a program written in tcl that calls -the llvm-runtests procedure on each test file. The -llvm-runtests procedure is defined in -llvm/test/lib/llvm-dg.exp. Any directory that contains only -directories does not need the dg.exp file.

+

In order for DejaGNU to work, each directory of tests must have a + dg.exp file. DejaGNU looks for this file to determine how to run the + tests. This file is just a Tcl script and it can do anything you want, but + we've standardized it for the LLVM regression tests. It simply loads a Tcl + library (test/lib/llvm.exp) and calls the llvm_runtests + function defined in that library with a list of file names to run. The names + are obtained by using Tcl's glob command. Any directory that contains only + directories does not need the dg.exp file.

-

In order for a test to be run, it must contain information within -the test file on how to run the test. These are called RUN -lines. Run lines are specified in the comments of the test program -using the keyword RUN followed by a colon, and lastly the -commands to execute. These commands will be executed in a bash script, -so any bash syntax is acceptable. You can specify as many RUN lines as -necessary. Each RUN line translates to one line in the resulting bash -script. Below is an example of legal RUN lines in a .ll -file:

-
-; RUN: llvm-as < %s | llvm-dis > %t1
-; RUN: llvm-dis < %s.bc-13 > %t2
-; RUN: diff %t1 %t2
-
-

There are a couple patterns within a RUN line that the -llvm-runtest procedure looks for and replaces with the appropriate -syntax:

+

The llvm-runtests function lookas at each file that is passed to + it and gathers any lines together that match "RUN:". This are the "RUN" lines + that specify how the test is to be run. So, each test script must contain + RUN lines if it is to do anything. If there are no RUN lines, the + llvm-runtests function will issue an error and the test will + fail.

-
-
%p
-
The path to the source directory. This is for locating -any supporting files that are not generated by the test, but used by -the test.
-
%s
-
The test file.
+

RUN lines are specified in the comments of the test program using the + keyword RUN followed by a colon, and lastly the command (pipeline) + to execute. Together, these lines form the "script" that + llvm-runtests executes to run the test case. The syntax of the + RUN lines is similar to a shell's syntax for pipelines including I/O + redirection and variable substitution. However, even though these lines + may look like a shell script, they are not. RUN lines are interpreted + directly by the Tcl exec command. They are never executed by a + shell. Consequently the syntax differs from normal shell script syntax in a + few ways. You can specify as many RUN lines as needed.

-
%t
-
Temporary filename: testscript.test_filename.tmp, where -test_filename is the name of the test file. All temporary files are -placed in the Output directory within the directory the test is -located.
+

Each RUN line is executed on its own, distinct from other lines unless + its last character is \. This continuation character causes the RUN + line to be concatenated with the next one. In this way you can build up long + pipelines of commands without making huge line lengths. The lines ending in + \ are concatenated until a RUN line that doesn't end in \ is + found. This concatenated set or RUN lines then constitutes one execution. + Tcl will substitute variables and arrange for the pipeline to be executed. If + any process in the pipeline fails, the entire line (and test case) fails too. +

-
%prcontext
-
Path to a script that performs grep -C. Use this since not all -platforms support grep -C.
+

Below is an example of legal RUN lines in a .ll file:

+ 
+  ; RUN: llvm-as < %s | llvm-dis > %t1
+  ; RUN: llvm-dis < %s.bc-13 > %t2
+  ; RUN: diff %t1 %t2
+
+
-
%llvmgcc
Full path to the llvm-gcc executable.
-
%llvmgxx
Full path to the llvm-g++ executable.
- + +
Vars And Substitutions
+
+

With a RUN line there are a number of substitutions that are permitted. In + general, any Tcl variable that is available in the substitute + function (in test/lib/llvm.exp) can be substituted into a RUN line. + To make a substitution just write the variable's name preceded by a $. + Additionally, for compatibility reasons with previous versions of the test + library, certain names can be accessed with an alternate syntax: a % prefix. + These alternates are deprecated and may go away in a future version. +

+ Here are the available variable names. The alternate syntax is listed in + parentheses.

+
+
$test (%s)
+
The full path to the test case's source. This is suitable for passing + on the command line as the input to an llvm tool.
+
$srcdir
+
The source directory from where the "make check" was run.
+
objdir
+
The object directory that corresponds to the $srcdir.
+
subdir
+
A partial path from the test directory that contains the + sub-directory that contains the test source being executed.
+
srcroot
+
The root directory of the LLVM src tree.
+
objroot
+
The root directory of the LLVM object tree. This could be the same + as the srcroot.
+
path
+
The path to the directory that contains the test case source. This is + for locating any supporting files that are not generated by the test, but + used by the test.
+
tmp
+
The path to a temporary file name that could be used for this test case. + The file name won't conflict with other test cases. You can append to it if + you need multiple temporaries. This is useful as the destination of some + redirected output.
+
llvmlibsdir (%llvmlibsdir)
+
The directory where the LLVM libraries are located.
+
target_triplet (%target_triplet)
+
The target triplet that corresponds to the current host machine (the one + running the test cases). This should probably be called "host".
+
prcontext (%prcontext)
+
Path to the prcontext tcl script that prints some context around a + line that matches a pattern. This isn't strictly necessary as the test suite + is run with its PATH altered to include the test/Scripts directory where + the prcontext script is located. Note that this script is similar to + grep -C but you should use the prcontext script because + not all platforms support grep -C.
+
llvmgcc (%llvmgcc)
+
The full path to the llvm-gcc executable as specified in the + configured LLVM environment
+
llvmgxx (%llvmgxx)
+
The full path to the llvm-gxx executable as specified in the + configured LLVM environment
+
llvmgcc_version (%llvmgcc_version)
+
The full version number of the llvm-gcc executable.
+
llvmgccmajvers (%llvmgccmajvers)
+
The major version number of the llvm-gcc executable.
+
gccpath
+
The full path to the C compiler used to build LLVM. Note that + this might not be gcc.
+
gxxpath
+
The full path to the C++ compiler used to build LLVM. Note that + this might not be g++.
+
compile_c (%compile_c)
+
The full command line used to compile LLVM C source code. This has all + the configured -I, -D and optimization options.
+
compile_cxx (%compile_cxx)
+
The full command used to compile LLVM C++ source code. This has + all the configured -I, -D and optimization options.
+
link (%link)
+
This full link command used to link LLVM executables. This has all the + configured -I, -L and -l options.
+
shlibext (%shlibext)
+
The suffix for the host platforms share library (dll) files. This + includes the period as the first character.
+
+

To add more variables, two things need to be changed. First, add a line in + the test/Makefile that creates the site.exp file. This will + "set" the variable as a global in the site.exp file. Second, in the + test/lib/llvm.exp file, in the substitute proc, add the variable name + to the list of "global" declarations at the beginning of the proc. That's it, + the variable can then be used in test scripts.

+
+ + +
Other Features
+
+

To make RUN line writing easier, there are several shell scripts located + in the llvm/test/Scripts directory. For example:

+
+
ignore
+
This script runs its arguments and then always returns 0. This is useful + in cases where the test needs to cause a tool to generate an error (e.g. to + check the error output). However, any program in a pipeline that returns a + non-zero result will cause the test to fail. This script overcomes that + issue and nicely documents that the test case is purposefully ignoring the + result code of the tool
+
not
+
This script runs its arguments and then inverts the result code from + it. Zero result codes become 1. Non-zero result codes become 0. This is + useful to invert the result of a grep. For example "not grep X" means + succeed only if you don't find X in the input.
+
-

There are also several scripts in the llvm/test/Scripts directory -that you might find useful when writing RUN lines.

+

Sometimes it is necessary to mark a test case as "expected fail" or XFAIL. + You can easily mark a test as XFAIL just by including XFAIL: on a + line near the top of the file. This signals that the test case should succeed + if the test fails. Such test cases are counted separately by DejaGnu. To + specify an expected fail, use the XFAIL keyword in the comments of the test + program followed by a colon and one or more regular expressions (separated by + a comma). The regular expressions allow you to XFAIL the test conditionally + by host platform. The regular expressions following the : are matched against + the target triplet or llvmgcc version number for the host machine. If there is + a match, the test is expected to fail. If not, the test is expected to + succeed. To XFAIL everywhere just specify XFAIL: *. When matching + the llvm-gcc version, you can specify the major (e.g. 3) or full version + (i.e. 3.4) number. Here is an example of an XFAIL line:

+ 
+   ; XFAIL: darwin,sun,llvmgcc4
+
-

Lastly, you can easily mark a test that is expected to fail on a -specific platform or with a specific version of llvmgcc by using the - XFAIL keyword. Xfail lines are -specified in the comments of the test program using XFAIL, -followed by a colon, and one or more regular expressions (separated by -a comma) that will match against the target triplet or llvmgcc version for the -machine. You can use * to match all targets. You can specify the major or full - version (i.e. 3.4) for llvmgcc. Here is an example of an -XFAIL line:

-
-; XFAIL: darwin,sun,llvmgcc4
-
+

To make the output more useful, the llvm_runtest function wil + scan the lines of the test case for ones that contain a pattern that matches + PR[0-9]+. This is the syntax for specifying a PR (Problem Report) number that + is related to the test case. The numer after "PR" specifies the LLVM bugzilla + number. When a PR number is specified, it will be used in the pass/fail + reporting. This is useful to quickly get some context when a test fails.

+ +

Finally, any line that contains "END." will cause the special + interpretation of lines to terminate. This is generally done right after the + last RUN: line. This has two side effects: (a) it prevents special + interpretation of lines that are part of the test program, not the + instructions to the test case, and (b) it speeds things up for really big test + cases by avoiding interpretation of the remainder of the file.