2004-04-23 Andrew Cagney * gdb.base/call-sc.exp: New test of scalar call/return values. * gdb.base/call-sc.c: Ditto. Index: gdb.base/call-sc.c =================================================================== RCS file: gdb.base/call-sc.c diff -N gdb.base/call-sc.c --- /dev/null 1 Jan 1970 00:00:00 -0000 +++ gdb.base/call-sc.c 23 Apr 2004 23:32:32 -0000 @@ -0,0 +1,83 @@ +/* This testcase is part of GDB, the GNU debugger. + + Copyright 2004 Free Software Foundation, Inc. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + +*/ + +/* Useful abreviations. */ +typedef void t; +typedef char tc; +typedef short ts; +typedef int ti; +typedef long tl; +typedef long long tll; +typedef float tf; +typedef double td; +typedef long double tld; +typedef enum { e = '1' } te; + +/* Force the type of each field. */ +#ifndef T +typedef t T; +#endif + +T foo = '1', L; + +T fun() +{ + return foo; +} + +#ifdef PROTOTYPES +void Fun(T foo) +#else +void Fun(foo) + T foo; +#endif +{ + L = foo; +} + +zed () +{ + L = 'Z'; +} + +int main() +{ +#ifdef usestubs + set_debug_traps(); + breakpoint(); +#endif + int i; + + Fun(foo); + + /* An infinite loop that first clears all the variables and then + calls the function. This "hack" is to make re-testing easier - + "advance fun" is guaranteed to have always been preceeded by a + global variable clearing zed call. */ + + zed (); + while (1) + { + L = fun (); + zed (); + } + + return 0; +} Index: gdb.base/call-sc.exp =================================================================== RCS file: gdb.base/call-sc.exp diff -N gdb.base/call-sc.exp --- /dev/null 1 Jan 1970 00:00:00 -0000 +++ gdb.base/call-sc.exp 23 Apr 2004 23:32:32 -0000 @@ -0,0 +1,487 @@ +# This testcase is part of GDB, the GNU debugger. + +# Copyright 2004 Free Software Foundation, Inc. + +# This program is free software; you can redistribute it and/or modify +# it under the terms of the GNU General Public License as published by +# the Free Software Foundation; either version 2 of the License, or +# (at your option) any later version. +# +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. +# +# You should have received a copy of the GNU General Public License +# along with this program; if not, write to the Free Software +# Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + +# Test "return", "finish", and "call" of functions that a scalar (int, +# float, enum) and/or take a single scalar parameter. + +if $tracelevel then { + strace $tracelevel +} + +set prms_id 0 +set bug_id 0 + +# Some targets can't call functions, so don't even bother with this +# test. + +if [target_info exists gdb,cannot_call_functions] { + setup_xfail "*-*-*" + fail "This target can not call functions" + continue +} + +set testfile "call-sc" +set srcfile ${testfile}.c +set binfile ${objdir}/${subdir}/${testfile} + +# Create and source the file that provides information about the +# compiler used to compile the test case. + +if [get_compiler_info ${binfile}] { + return -1; +} + +# Use the file name, compiler and tuples to set up any needed KFAILs. + +proc setup_kfails { file tuples bug } { + global testfile + if [string match $file $testfile] { + foreach f $tuples { setup_kfail $f $bug } + } +} + +proc setup_compiler_kfails { file compiler format tuples bug } { + global testfile + if {[string match $file $testfile] && [test_compiler_info $compiler] && [test_debug_format $format]} { + foreach f $tuples { setup_kfail $f $bug } + } +} + +# Compile a variant of scalars.c using TYPE to specify the type of the +# parameter and return-type. Run the compiled program up to "main". +# Also updates the global "testfile" to reflect the most recent build. + +proc start_scalars_test { type } { + global testfile + global srcfile + global binfile + global objdir + global subdir + global srcdir + global gdb_prompt + global expect_out + + # Create the additional flags + set flags "debug additional_flags=-DT=${type}" + set testfile "call-sc-${type}" + + set binfile ${objdir}/${subdir}/${testfile} + if { [gdb_compile "${srcdir}/${subdir}/${srcfile}" "${binfile}" executable "${flags}"] != "" } { + # built the second test case since we can't use prototypes + warning "Prototypes not supported, rebuilding with -DNO_PROTOTYPES" + if { [gdb_compile "${srcdir}/${subdir}/${srcfile}" "${binfile}" executable "${flags} additional_flags=-DNO_PROTOTYPES"] != "" } { + gdb_suppress_entire_file "Testcase compile failed, so all tests in this file will automatically fail." + } + } + + # Start with a fresh gdb. + gdb_exit + gdb_start + gdb_reinitialize_dir $srcdir/$subdir + gdb_load ${binfile} + + # Make certain that the output is consistent + gdb_test "set print sevenbit-strings" "" \ + "set print sevenbit-strings; ${testfile}" + gdb_test "set print address off" "" \ + "set print address off; ${testfile}" + gdb_test "set width 0" "" \ + "set width 0; ${testfile}" + + # Advance to main + if { ![runto_main] } then { + gdb_suppress_tests; + } + + # Get the debug format + get_debug_format + + # check that type matches what was passed in + set test "ptype; ${testfile}" + set foo_t "xxx" + gdb_test_multiple "ptype ${type}" "${test}" { + -re "type = (\[^\\r\\n\]*).*$gdb_prompt $" { + set foo_t "$expect_out(1,string)" + pass "$test (${foo_t})" + } + } + gdb_test "ptype foo" "type = ${foo_t}" "ptype foo; ${testfile} $expect_out(1,string)" +} + + +# Given N (0..25), return the corresponding alphabetic letter in lower +# or upper case. This is ment to be i18n proof. + +proc i2a { n } { + return [string range "abcdefghijklmnopqrstuvwxyz" $n $n] +} + +proc I2A { n } { + return [string toupper [i2a $n]] +} + + +# Use the file name, compiler and tuples to set up any needed KFAILs. + +proc setup_kfails { file tuples bug } { + global testfile + if [string match $file $testfile] { + foreach f $tuples { setup_kfail $f $bug } + } +} + +proc setup_compiler_kfails { file compiler format tuples bug } { + global testfile + if {[string match $file $testfile] && [test_compiler_info $compiler] && [test_debug_format $format]} { + foreach f $tuples { setup_kfail $f $bug } + } +} + +# Test GDB's ability to make inferior function calls to functions +# returning (or passing) in a single scalar. + +# start_scalars_test() will have previously built a program with a +# specified scalar type. To ensure robustness of the output, "p/c" is +# used. + +# This tests the code paths "which return-value convention?" and +# "extract return-value from registers" called by "infcall.c". + +proc test_scalar_calls { } { + global testfile + global gdb_prompt + + # Check that GDB can always extract a scalar-return value from an + # inferior function call. Since GDB always knows the location of + # an inferior function call's return value these should never fail + + # Implemented by calling the parameterless function "fun" and then + # examining the return value printed by GDB. + + set tests "call ${testfile}" + + # Call fun, checking the printed return-value. + gdb_test "p/c fun()" "= 49 '1'" "p/c fun(); ${tests}" + + # Check that GDB can always pass a structure to an inferior function. + # This test can never fail. + + # Implemented by calling the one parameter function "Fun" which + # stores its parameter in the global variable "L". GDB then + # examining that global to confirm that the value is as expected. + + gdb_test "call Fun(foo)" "" "call Fun(foo); ${tests}" + gdb_test "p/c L" " = 49 '1'" "p/c L; ${tests}" +} + +# Test GDB's ability to both return a function (with "return" or +# "finish") and correctly extract/store any corresponding +# return-value. + +# Check that GDB can consistently extract/store structure return +# values. There are two cases - returned in registers and returned in +# memory. For the latter case, the return value can't be found and a +# failure is "expected". However GDB must still both return the +# function and display the final source and line information. + +# N identifies the number of elements in the struct that will be used +# for the test case. FAILS is a list of target tuples that will fail +# this test. + +# This tests the code paths "which return-value convention?", "extract +# return-value from registers", and "store return-value in registers". +# Unlike "test struct calls", this test is expected to "fail" when the +# return-value is in memory (GDB can't find the location). The test +# is in three parts: test "return"; test "finish"; check that the two +# are consistent. GDB can sometimes work for one command and not the +# other. + +proc test_scalar_returns { } { + global gdb_prompt + global testfile + + set tests "return ${testfile}" + + + # Check that "return" works. + + # GDB must always force the return of a function that has + # a struct result. Dependant on the ABI, it may, or may not be + # possible to store the return value in a register. + + # The relevant code looks like "L{n} = fun{n}()". The test forces + # "fun{n}" to "return" with an explicit value. Since that code + # snippet will store the the returned value in "L{n}" the return + # is tested by examining "L{n}". This assumes that the + # compiler implemented this as fun{n}(&L{n}) and hence that when + # the value isn't stored "L{n}" remains unchanged. Also check for + # consistency between this and the "finish" case. + + # Get into a call of fun + gdb_test "advance fun" \ + "fun .*\[\r\n\]+\[0-9\].*return foo.*" \ + "advance to fun for return; ${tests}" + + # Check that the program invalidated the relevant global. + gdb_test "p/c L" " = 90 'Z'" "zed L for return; ${tests}" + + # Force the "return". This checks that the return is always + # performed, and that GDB correctly reported this to the user. + # GDB 6.0 and earlier, when the return-value's location wasn't + # known, both failed to print a final "source and line" and misplaced + # the frame ("No frame"). + + # The test is writen so that it only reports one FAIL/PASS for the + # entire operation. The value returned is checked further down. + # "return_value_unknown", if non-empty, records why GDB realised + # that it didn't know where the return value was. + + set test "return foo; ${tests}" + set return_value_unknown 0 + set return_value_unimplemented 0 + setup_kfails call-sc-tld i*86-*-* gdb/1623 + gdb_test_multiple "return foo" "${test}" { + -re "The location" { + # Ulgh, a struct return, remember this (still need prompt). + set return_value_unknown 1 + exp_continue + } + -re "A structure or union" { + # Ulgh, a struct return, remember this (still need prompt). + set return_value_unknown 1 + # Double ulgh. Architecture doesn't use return_value and + # hence hasn't implemented small structure return. + set return_value_unimplemented 1 + exp_continue + } + -re "Make fun return now.*y or n. $" { + gdb_test_multiple "y" "${test}" { + -re "L *= fun.*${gdb_prompt} $" { + # Need to step off the function call + gdb_test "next" "zed.*" "${test}" + } + -re "L[expr + 1] *= fun[expr + 1].*${gdb_prompt} $" { + pass "${test}" + } + } + } + } + + # Check that the return-value is as expected. At this stage we're + # just checking that GDB has returned a value consistent with + # "return_value_unknown" set above. + + set test "value foo returned; ${tests}" + setup_kfails call-sc-tc x86_64-*-* gdb/1624 + setup_kfails call-sc-ts x86_64-*-* gdb/1624 + setup_kfails call-sc-ti x86_64-*-* gdb/1624 + setup_kfails call-sc-tl x86_64-*-* gdb/1624 + setup_kfails call-sc-tll x86_64-*-* gdb/1624 + setup_kfails call-sc-tld x86_64-*-* gdb/1624 + setup_kfails call-sc-te x86_64-*-* gdb/1624 + setup_kfails call-sc-tf i*86-*-* gdb/1623 + setup_kfails call-sc-td i*86-*-* gdb/1623 + setup_kfails call-sc-tld i*86-*-* gdb/1623 + gdb_test_multiple "p/c L" "${test}" { + -re " = 49 '1'.*${gdb_prompt} $" { + if $return_value_unknown { + # This contradicts the above claim that GDB didn't + # know the location of the return-value. + fail "${test}" + } else { + pass "${test}" + } + } + -re " = 90 .*${gdb_prompt} $" { + if $return_value_unknown { + # The struct return case. Since any modification + # would be by reference, and that can't happen, the + # value should be unmodified and hence Z is expected. + # Is this a reasonable assumption? + pass "${test}" + } else { + # This contradicts the above claim that GDB knew + # the location of the return-value. + fail "${test}" + } + } + -re ".*${gdb_prompt} $" { + if $return_value_unimplemented { + # What a suprize. The architecture hasn't implemented + # return_value, and hence has to fail. + kfail "$test" gdb/1444 + } else { + fail "$test" + } + } + } + + # Check that a "finish" works. + + # This is almost but not quite the same as "call struct funcs". + # Architectures can have subtle differences in the two code paths. + + # The relevant code snippet is "L{n} = fun{n}()". The program is + # advanced into a call to "fun{n}" and then that function is + # finished. The returned value that GDB prints, reformatted using + # "p/c", is checked. + + # Get into "fun()". + gdb_test "advance fun" \ + "fun .*\[\r\n\]+\[0-9\].*return foo.*" \ + "advance to fun for finish; ${tests}" + + # Check that the program invalidated the relevant global. + gdb_test "p/c L" " = 90 'Z'" "zed L for finish; ${tests}" + + # Finish the function, set 'finish_value_unknown" to non-empty if the + # return-value was not found. + set test "finish foo; ${tests}" + set finish_value_unknown 0 + gdb_test_multiple "finish" "${test}" { + -re "Value returned is .*${gdb_prompt} $" { + pass "${test}" + } + -re "Cannot determine contents.*${gdb_prompt} $" { + # Expected bad value. For the moment this is ok. + set finish_value_unknown 1 + pass "${test}" + } + } + + # Re-print the last (return-value) using the more robust + # "p/c". If no return value was found, the 'Z' from the previous + # check that the variable was cleared, is printed. + set test "value foo finished; ${tests}" + gdb_test_multiple "p/c" "${test}" { + -re " = 49 '1'\[\r\n\]+${gdb_prompt} $" { + if $finish_value_unknown { + # This contradicts the above claim that GDB didn't + # know the location of the return-value. + fail "${test}" + } else { + pass "${test}" + } + } + -re " = 90 'Z'\[\r\n\]+${gdb_prompt} $" { + # The value didn't get found. This is "expected". + if $finish_value_unknown { + pass "${test}" + } else { + # This contradicts the above claim that GDB did + # know the location of the return-value. + fail "${test}" + } + } + } + + # Finally, check that "return" and finish" have consistent + # behavior. + + # Since both "return" and "finish" use equivalent "which + # return-value convention" logic, both commands should have + # identical can/can-not find return-value messages. + + # Note that since "call" and "finish" use common code paths, a + # failure here is a strong indicator of problems with "store + # return-value" code paths. Suggest looking at "return_value" + # when investigating a fix. + + set test "return and finish use same convention; ${tests}" + if {$finish_value_unknown == $return_value_unknown} { + pass "${test}" + } else { + kfail gdb/1444 "${test}" + } +} + +# ABIs pass anything >8 or >16 bytes in memory but below that things +# randomly use register and/and structure conventions. Check all +# possible sized char scalars in that range. But only a restricted +# range of the other types. + +# NetBSD/PPC returns "unnatural" (3, 5, 6, 7) sized scalars in memory. + +# d10v is weird. 5/6 byte scalars go in memory. 2 or more char +# scalars go in memory. Everything else is in a register! + +# Test every single char struct from 1..17 in size. This is what the +# original "scalars" test was doing. + +start_scalars_test tc +test_scalar_calls +test_scalar_returns + + +# Let the fun begin. + +# Assuming that any integer struct larger than 8 bytes goes in memory, +# come up with many and varied combinations of a return struct. For +# "struct calls" test just beyond that 8 byte boundary, for "struct +# returns" test up to that boundary. + +# For floats, assumed that up to two struct elements can be stored in +# floating point registers, regardless of their size. + +# The approx size of each structure it is computed assumed that tc=1, +# ts=2, ti=4, tl=4, tll=8, tf=4, td=8, tld=16, and that all fields are +# naturally aligned. Padding being added where needed. Note that +# these numbers are just approx, the d10v has ti=2, a 64-bit has has +# tl=8. + +# Approx size: 2, 4, ... +start_scalars_test ts +test_scalar_calls +test_scalar_returns + +# Approx size: 4, 8, ... +start_scalars_test ti +test_scalar_calls +test_scalar_returns + +# Approx size: 4, 8, ... +start_scalars_test tl +test_scalar_calls +test_scalar_returns + +# Approx size: 8, 16, ... +start_scalars_test tll +test_scalar_calls +test_scalar_returns + +# Approx size: 4, 8, ... +start_scalars_test tf +test_scalar_calls +test_scalar_returns + +# Approx size: 8, 16, ... +start_scalars_test td +test_scalar_calls +test_scalar_returns + +# Approx size: 16, 32, ... +start_scalars_test tld +test_scalar_calls +test_scalar_returns + +# Approx size: 4, 8, ... +start_scalars_test te +test_scalar_calls +test_scalar_returns + +return 0