#   Copyright (C) 1997-2021 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 3 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 GCC; see the file COPYING3.  If not see
# <http://www.gnu.org/licenses/>.

# Verify various kinds of gcov output: line counts, branch percentages,
# and call return percentages.  None of this is language-specific.

global GCOV

#
# clean-gcov-file -- delete a working file the compiler creates for gcov
#
# TESTCASE is the name of the test.
# SUFFIX is file suffix

proc clean-gcov-file { testcase suffix } {
    set basename [file tail $testcase]
    set base [file rootname $basename]
    remote_file host delete $base.$suffix
}

#
# clean-gcov -- delete the working files the compiler creates for gcov
#
# TESTCASE is the name of the test.
#
proc clean-gcov { testcase } {
    clean-gcov-file $testcase "gcno"
    clean-gcov-file $testcase "gcda"
    clean-gcov-file $testcase "h.gcov"
    remote_file host delete "$testcase.gcov"
}

#
# verify-lines -- check that line counts are as expected
#
# TESTNAME is the name of the test, including unique flags.
# TESTCASE is the name of the test file.
# FILE is the name of the gcov output file.
#
proc verify-lines { testname testcase file } {
    #send_user "verify-lines\n"
    global subdir

    set failed 0
    set fd [open $file r]
    while { [gets $fd line] >= 0 } {
        # We want to match both "-" and "#####" as count as well as numbers,
        # since we want to detect lines that shouldn't be marked as covered.
	if [regexp "^ *(\[^:]*): *(\[0-9\\-#]+):.*count\\((\[0-9\\-#=\\.kMGTPEZY\*]+)\\)(.*)" \
		"$line" all is n shouldbe rest] {
	    if [regexp "^ *{(.*)}" $rest all xfailed] {
		switch [dg-process-target $xfailed] {
		    "N" { continue }
		    "F" { setup_xfail "*-*-*" }
		}
	    }
	    if { $is == "" } {
		fail "$testname line $n: no data available"
		incr failed
	    } elseif { $is != $shouldbe } {
		fail "$testname line $n: is $is:should be $shouldbe"
		incr failed
	    } else {
		pass "$testname count for line $n"
	    }
	}
    }
    close $fd
    return $failed
}


#
# verify-branches -- check that branch percentages are as expected
#
# TESTNAME is the name of the test, including unique flags.
# TESTCASE is the name of the test file.
# FILE is the name of the gcov output file.
#
# Checks are based on comments in the source file.  This means to look for
# branch percentages 10 or 90, 20 or 80, and # 70 or 30:
#     /* branch(10, 20, 70) */
# This means that all specified percentages should have been seen by now:
#     /* branch(end) */
# All specified percentages must also be seen by the next branch(n) or
# by the end of the file.
#
# Each check depends on the compiler having generated the expected
# branch instructions.  Don't check for branches that might be
# optimized away or replaced with predicated instructions.
#
proc verify-branches { testname testcase file } {
    #send_user "verify-branches\n"

    set failed 0
    set shouldbe ""
    set fd [open $file r]
    set n 0
    while { [gets $fd line] >= 0 } {
	regexp "^\[^:\]+: *(\[0-9\]+):" "$line" all n
	if [regexp "branch" $line] {
	    verbose "Processing branch line $n: $line" 3
	    if [regexp "branch\\((\[0-9 \]+)\\)" "$line" all new_shouldbe] {
		# All percentages in the current list should have been seen.
		if {[llength $shouldbe] != 0} {
		    fail "$testname line $n: expected branch percentages not found: $shouldbe"
		    incr failed
		    set shouldbe ""
		}
		set shouldbe $new_shouldbe
		#send_user "$n: looking for: $shouldbe\n"
	        # Record the percentages to check for. Replace percentage
		# n > 50 with 100-n, since block ordering affects the
		# direction of a branch.
		for {set i 0} {$i < [llength $shouldbe]} {incr i} {
		    set num [lindex $shouldbe $i]
		    if {$num > 50} {
			set shouldbe [lreplace $shouldbe $i $i [expr 100 - $num]]
		    }
		}
	    } elseif [regexp "branch +\[0-9\]+ taken (-\[0-9\]+)%" "$line" \
			all taken] {
		# Percentages should never be negative.
		fail "$testname line $n: negative percentage: $taken"
		incr failed
	    } elseif [regexp "branch +\[0-9\]+ taken (\[0-9\]+)%" "$line" \
			all taken] {
		#send_user "$n: taken = $taken\n"
		# Percentages should never be greater than 100.
		if {$taken > 100} {
		    fail "$testname line $n: branch percentage greater than 100: $taken"
		    incr failed
		}
		if {$taken > 50} {
		    set taken [expr 100 - $taken]
		}
		# If this percentage is one to check for then remove it
		# from the list.  It's normal to ignore some reports.
		set i [lsearch $shouldbe $taken]
		if {$i != -1} {
		    set shouldbe [lreplace $shouldbe $i $i]
		}
	    } elseif [regexp "branch\\(end\\)" "$line"] {
		# All percentages in the list should have been seen by now.
		if {[llength $shouldbe] != 0} {
		    fail "$testname line n: expected branch percentages not found: $shouldbe"
		    incr failed
		}
		set shouldbe ""
	    }
	}
    }
    # All percentages in the list should have been seen.
    if {[llength $shouldbe] != 0} {
	fail "$testname line $n: expected branch percentages not found: $shouldbe"
	incr failed
    }
    close $fd
    return $failed
}

#
# verify-calls -- check that call return percentages are as expected
#
# TESTNAME is the name of the test, including unique flags.
# TESTCASE is the name of the test file.
# FILE is the name of the gcov output file.
#
# Checks are based on comments in the source file.  This means to look for
# call return percentages 50, 20, 33:
#     /* returns(50, 20, 33) */
# This means that all specified percentages should have been seen by now:
#     /* returns(end) */
# All specified percentages must also be seen by the next returns(n) or
# by the end of the file.
#
# Each check depends on the compiler having generated the expected
# call instructions.  Don't check for calls that are inserted by the
# compiler or that might be inlined.
#
proc verify-calls { testname testcase file } {
    #send_user "verify-calls\n"

    set failed 0
    set shouldbe ""
    set fd [open $file r]
    set n 0
    while { [gets $fd line] >= 0 } {
	regexp "^\[^:\]+: *(\[0-9\]+):" "$line" all n
	if [regexp "return" $line] {
	    verbose "Processing returns line $n: $line" 3
	    if [regexp "returns\\((\[0-9 \]+)\\)" "$line" all new_shouldbe] {
		# All percentages in the current list should have been seen.
		if {[llength $shouldbe] != 0} {
		    fail "$testname line $n: expected return percentages not found: $shouldbe"
		    incr failed
		    set shouldbe ""
		}
	        # Record the percentages to check for.
		set shouldbe $new_shouldbe
	    } elseif [regexp "call +\[0-9\]+ returned (-\[0-9\]+)%" "$line" \
			all returns] {
		# Percentages should never be negative.
		fail "$testname line $n: negative percentage: $returns"
		incr failed
	    } elseif [regexp "call +\[0-9\]+ returned (\[0-9\]+)%" "$line" \
			all returns] {
		# For branches we check that percentages are not greater than
		# 100 but call return percentages can be, as for setjmp(), so
		# don't count that as an error.
		#
		# If this percentage is one to check for then remove it
		# from the list.  It's normal to ignore some reports.
		set i [lsearch $shouldbe $returns]
		if {$i != -1} {
		    set shouldbe [lreplace $shouldbe $i $i]
		}
	    } elseif [regexp "returns\\(end\\)" "$line"] {
		# All percentages in the list should have been seen by now.
		if {[llength $shouldbe] != 0} {
		    fail "$testname line $n: expected return percentages not found: $shouldbe"
		    incr failed
		}
		set shouldbe ""
	    }
	}
    }
    # All percentages in the list should have been seen.
    if {[llength $shouldbe] != 0} {
	fail "$testname line $n: expected return percentages not found: $shouldbe"
	incr failed
    }
    close $fd
    return $failed
}

proc gcov-pytest-format-line { args } {
    global subdir

    set testcase [lindex $args 0]
    set pytest_script [lindex $args 1]
    set output_line [lindex $args 2]

    set index [string first "::" $output_line]
    set test_output [string range $output_line [expr $index + 2] [string length $output_line]]

    return "$subdir/$testcase ${pytest_script}::${test_output}"
}

# Call by dg-final to run gcov --json-format which produces a JSON file
# that is later analysed by a pytest Python script.
# We pass filename of a test via GCOV_PATH environment variable.

proc run-gcov-pytest { args } {
    global GCOV
    global srcdir subdir
    # Extract the test file name from the arguments.
    set testcase [lindex $args 0]

    verbose "Running $GCOV $testcase in $srcdir/$subdir" 2
    set testcase [remote_download host $testcase]
    set result [remote_exec host $GCOV "$testcase -i"]

    set pytest_cmd "python3 -m pytest --color=no -rap -s --tb=no"
    set result [remote_exec host "$pytest_cmd --version"]
    set status [lindex $result 0]
    if { $status != 0 } then {
      unsupported "$subdir/$testcase run-gcov-pytest python3 pytest missing"
      return
    }

    set pytest_script [lindex $args 1]
    setenv GCOV_PATH $testcase
    verbose "pytest_script: $srcdir $subdir $pytest_script" 2
    spawn -noecho python3 -m pytest --color=no -rap -s --tb=no $srcdir/$subdir/$pytest_script

    set prefix "\[^\r\n\]*"
    expect {
      -re "FAILED($prefix)\[^\r\n\]+\r\n" {
       set output [gcov-pytest-format-line $testcase $pytest_script $expect_out(1,string)]
       fail $output
       exp_continue
      }
      -re "ERROR($prefix)\[^\r\n\]+\r\n" {
       set output [gcov-pytest-format-line $testcase $pytest_script $expect_out(1,string)]
       fail $output
       exp_continue
      }
      -re "PASSED($prefix)\[^\r\n\]+\r\n" {
       set output [gcov-pytest-format-line $testcase $pytest_script $expect_out(1,string)]
       pass $output
       exp_continue
      }
    }

    clean-gcov $testcase
}

# Called by dg-final to run gcov and analyze the results.
#
# ARGS consists of the optional strings "branches" and/or "calls",
# (indicating that these things should be verified) followed by a 
# list of arguments to provide to gcov, including the name of the
# source file.

proc run-gcov { args } {
    global GCOV
    global srcdir subdir

    set gcov_args ""
    set gcov_verify_calls 0
    set gcov_verify_branches 0
    set gcov_verify_lines 1
    set gcov_verify_intermediate 0
    set gcov_remove_gcda 0
    set xfailed 0

    foreach a $args {
	if { $a == "calls" } {
	  set gcov_verify_calls 1
	} elseif { $a == "branches" } {
	  set gcov_verify_branches 1
	} elseif { $a == "intermediate" } {
	  set gcov_verify_intermediate 1
	  set gcov_verify_calls 0
	  set gcov_verify_branches 0
	  set gcov_verify_lines 0
	} elseif { $a == "remove-gcda" } {
	  set gcov_remove_gcda 1
	} elseif { $gcov_args == "" } {
	    set gcov_args $a
	} else {
	    switch [dg-process-target $a] {
		"N" { return }
		"F" { set xfailed 1 }
	    }
	}
    }

    set testname [testname-for-summary]

    # Extract the test file name from the arguments.
    set testcase [lindex $gcov_args end]

    if { $gcov_remove_gcda } {
	verbose "Removing $testcase.gcda"
	clean-gcov-file $testcase "gcda"
    }

    verbose "Running $GCOV $testcase" 2
    set testcase [remote_download host $testcase]
    set result [remote_exec host $GCOV $gcov_args]
    if { [lindex $result 0] != 0 } {
	if { $xfailed } {
	    setup_xfail "*-*-*"
	}
	fail "$testname gcov failed: [lindex $result 1]"
	clean-gcov $testcase
	return
    }

    set builtin_index [string first "File '<built-in>'" $result]
    if { $builtin_index != -1 } {
        fail "$testname gcov failed: <built-in>.gcov should not be created"
        clean-gcov $testcase
        return
    }

    # Get the gcov output file after making sure it exists.
    set files [glob -nocomplain $testcase.gcov]
    if { $files == "" } {
	if { $xfailed } {
	    setup_xfail "*-*-*"
	}
        fail "$testname gcov failed: $testcase.gcov does not exist"
        clean-gcov $testcase
        return
    }
    remote_upload host $testcase.gcov $testcase.gcov

    # Check that line execution counts are as expected.
    if { $gcov_verify_lines } {
	# Check that line execution counts are as expected.
	set lfailed [verify-lines $testname $testcase $testcase.gcov]
    } else {
	set lfailed 0
    }

    # If requested via the .x file, check that branch and call information
    # is correct.
    if { $gcov_verify_branches } {
	set bfailed [verify-branches $testname $testcase $testcase.gcov]
    } else {
	set bfailed 0
    }
    if { $gcov_verify_calls } {
	set cfailed [verify-calls $testname $testcase $testcase.gcov]
    } else {
	set cfailed 0
    }
    if { $gcov_verify_intermediate } {
	# Check that intermediate format has the expected format
	set ifailed [verify-intermediate $testname $testcase $testcase.gcov]
    } else {
	set ifailed 0
    }

    # Report whether the gcov test passed or failed.  If there were
    # multiple failures then the message is a summary.
    set tfailed [expr $lfailed + $bfailed + $cfailed + $ifailed]
    if { $xfailed } {
	setup_xfail "*-*-*"
    }
    if { $tfailed > 0 } {
	fail "$testname gcov: $lfailed failures in line counts, $bfailed in branch percentages, $cfailed in return percentages, $ifailed in intermediate format"
	if { $xfailed } {
	    clean-gcov $testcase
	}
    } else {
	pass "$testname gcov"
	clean-gcov $testcase
    }
}