From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 14676 invoked by alias); 4 Nov 2014 22:50:29 -0000 Mailing-List: contact gdb-patches-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sourceware.org Received: (qmail 14662 invoked by uid 89); 4 Nov 2014 22:50:28 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-3.2 required=5.0 tests=AWL,BAYES_00,RCVD_IN_DNSWL_LOW,RP_MATCHES_RCVD,SPF_PASS autolearn=ham version=3.3.2 X-HELO: mail-ob0-f201.google.com Received: from mail-ob0-f201.google.com (HELO mail-ob0-f201.google.com) (209.85.214.201) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with (AES128-SHA encrypted) ESMTPS; Tue, 04 Nov 2014 22:50:27 +0000 Received: by mail-ob0-f201.google.com with SMTP id nt9so2142937obb.2 for ; Tue, 04 Nov 2014 14:50:25 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:from:mime-version:content-type :content-transfer-encoding:message-id:date:to:cc:subject:in-reply-to :references; bh=WKsVg0HBjqjPvAFdADXvM0L8Iv7ka9PnRK/wCdDYgKY=; b=J/D85qDOEMHLmZLr7i625MlkfUEQKM1HxTJomj/fDo9D3MMRB3G4cvji6f1gnO1H+v ezA4GEFAm5SBpv2xzMeglewwO+z2qG6nNGDnoafV96PqsL7ufIWaqvluBydyJzpIxvbJ dym2gkyaDAzKibGqZTFSnurPuvNgOiTt1+57NGPEMJhXrarBMOwP4g+xUY2HsE7AF9+0 zdcJO9vTPU8R6nNXz+knOowjsR3k1oIxdqwUNY8782yH9lVjwgfu4nmurrxaGAEwVdlC DUOHjHOhiSRT0iF4DRv5WzD4U8Moaq/jptdyuYn2eYTqWdvw1VYrhz/ts/9HUVp3nK0n Odkg== X-Gm-Message-State: ALoCoQk2jpCnD9pVLVErrYZg7xCc+dpvzn8ObhizHAUDjAvIW5uK8X2lQR+JMhw1DYuotOjfxPySV+HL2WrOCr7KB+rVRU6k4cgPY0rA8KhcrF62eM2a1lebBrfzNfywLGhCZbtjRT26sK96MTXPLoJV8STDsak7+ODLTm7LLdUc3lHxvNU/BmY= X-Received: by 10.50.111.170 with SMTP id ij10mr20232617igb.1.1415141425005; Tue, 04 Nov 2014 14:50:25 -0800 (PST) Received: from corpmail-nozzle1-1.hot.corp.google.com ([100.108.1.104]) by gmr-mx.google.com with ESMTPS id 5si34635yhd.6.2014.11.04.14.50.24 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 04 Nov 2014 14:50:24 -0800 (PST) Received: from ruffy2.mtv.corp.google.com ([172.17.128.107]) by corpmail-nozzle1-1.hot.corp.google.com with ESMTP id o2hPPBn1.1; Tue, 04 Nov 2014 14:50:24 -0800 From: Doug Evans MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-ID: <21593.22575.941029.980760@ruffy2.mtv.corp.google.com> Date: Tue, 04 Nov 2014 22:50:00 -0000 To: Yao Qi Cc: Subject: Re: [PATCH 2/6] DW attribute macro MACRO_AT_func and MACRO_AT_range In-Reply-To: <1414195968-3333-3-git-send-email-yao@codesourcery.com> References: <1414195968-3333-1-git-send-email-yao@codesourcery.com> <1414195968-3333-3-git-send-email-yao@codesourcery.com> X-IsSubscribed: yes X-SW-Source: 2014-11/txt/msg00082.txt.bz2 Yao Qi writes: > This patch addes DW macro attributes MACRO_AT_func and MACRO_AT_range > in dwarf assembler, which emits "DW_AT_low_pc func_start addr" and > "DW_AT_high_pc func_end addr". func_start and func_end are computed > automatically by proc function_range. > > These two attributes are pseudo attribute or macro attribute, which > means they are not standard dwarf attribute in dwarf spec. Then can > be substituted or expanded to standard attributes or macro attributes. > See details in the comments to them. Dwarf assembler is extended to > handle them. > > Now the attributes name/low_pc/high_pc can be replaced with > MACRO_AT_func like this: > > subprogram { > {name main} > {low_pc main_start addr} > {high_pc main_end addr} > } > > becomes: > > subprogram { > {MACRO_AT_func { main ${srcdir}/${subdir}/${srcfile} }} > } > > users don't have to worry about the start and end of function main, and > they only need to add a label main_label in main. > > gdb/testsuite: > > 2014-10-24 Yao Qi > > * lib/dwarf.exp (function_range): New procedure. > (Dwarf::_handle_macro_attribute): New procedure. > (Dwarf): Handle MACRO_AT_func and MACRO_AT_range. > --- > gdb/testsuite/lib/dwarf.exp | 128 +++++++++++++++++++++++++++++++++++++++++--- > 1 file changed, 122 insertions(+), 6 deletions(-) > > diff --git a/gdb/testsuite/lib/dwarf.exp b/gdb/testsuite/lib/dwarf.exp > index 4986f83..401e791 100644 > --- a/gdb/testsuite/lib/dwarf.exp > +++ b/gdb/testsuite/lib/dwarf.exp > @@ -86,6 +86,81 @@ proc build_executable_from_fission_assembler { testname executable sources optio > return 0 > } > > +# Return a list of expressions about function FUNC's address and length. > +# The first expression is the address of function FUNC, and the second > +# one is FUNC's length. SRC is the source file having function FUNC. > +# An internal label ${func}_label must be defined inside FUNC: > +# > +# int main (void) > +# { > +# asm ("main_label: .globl main_label"); > +# return 0; > +# } > +# > +# This label is needed to compute the start address of function FUNC. > +# If the compiler is gcc, we can do the following to get function start > +# and end address too: > +# > +# asm ("func_start: .globl func_start"); > +# static void func (void) {} > +# asm ("func_end: .globl func_end"); > +# > +# however, this isn't portable, because other compilers, such as clang, > +# may not guarantee the order of global asms and function. The code > +# becomes: > +# > +# asm ("func_start: .globl func_start"); > +# asm ("func_end: .globl func_end"); > +# static void func (void) {} > +# > + > +proc function_range { func src } { > + global decimal gdb_prompt > + > + set exe [standard_temp_file func_addr[pid].x] > + > + gdb_compile $src $exe executable {debug} > + > + gdb_exit > + gdb_start > + gdb_load "$exe" > + > + # Compute the label offset, and we can get the function start address > + # by "${func}_label - $func_label_offset". > + set func_label_offset "" > + set test "p ${func}_label - ${func}" > + gdb_test_multiple $test $test { > + -re ".* = ($decimal)\r\n$gdb_prompt $" { > + set func_label_offset $expect_out(1,string) > + } > + } > + > + # Compute the function length. > + global hex > + set func_length "" > + set test "disassemble $func" > + gdb_test_multiple $test $test { > + -re ".*$hex <\\+($decimal)>:\[^\r\n\]+\r\nEnd of assembler dump\.\r\n$gdb_prompt $" { > + set func_length $expect_out(1,string) > + } > + } > + > + # Compute the size of the last instruction. > + set test "x/2i $func+$func_length" > + gdb_test_multiple $test $test { > + -re ".*($hex) <$func\\+$func_length>:\[^\r\n\]+\r\n\[ \]+($hex).*\.\r\n$gdb_prompt $" { > + set start $expect_out(1,string) > + set end $expect_out(2,string) > + > + set func_length [expr $func_length + $end - $start] > + } > + } > + > + file delete $exe > + > + return [list "${func}_label - $func_label_offset" $func_length] > +} > + > # A DWARF assembler. > # > # All the variables in this namespace are private to the > @@ -121,6 +196,17 @@ proc build_executable_from_fission_assembler { testname executable sources optio > # This can either be the full name, like 'DW_AT_name', or a shortened > # name, like 'name'. These are fully equivalent. > # > +# Besides DWARF standard attributes, assembler supports 'macro' attribute > +# which will be substituted by one or more standard or macro attributes. > +# supported macro attributes are: > +# > +# - MACRO_AT_range { FUNC FILE } > +# It is substituted by DW_AT_low_pc and DW_AT_high_pc with the start and > +# end address of function FUNC in file FILE. > +# > +# - MACRO_AT_func { FUNC FILE } > +# It is substituted by DW_AT_name with FUNC and MACRO_AT_range. > +# > # If FORM is given, it should name a DW_FORM_ constant. > # This can either be the short form, like 'DW_FORM_addr', or a > # shortened version, like 'addr'. If the form is given, VALUE > @@ -473,6 +559,31 @@ namespace eval Dwarf { > } > } > > + proc _handle_macro_attribute { attr_name attr_value } { > + switch -exact -- $attr_name { > + MACRO_AT_func { > + _handle_attribute DW_AT_name [lindex $attr_value 0] \ > + DW_FORM_string > + > + _handle_macro_attribute MACRO_AT_range $attr_value > + } > + MACRO_AT_range { > + if {[llength $attr_value] != 2} { > + error "usage: $attr_name { func file }" > + } > + set func [lindex $attr_value 0] > + set src [lindex $attr_value 1] > + > + set result [function_range $func $src] > + _handle_attribute DW_AT_low_pc [lindex $result 0] \ > + DW_FORM_addr > + _handle_attribute DW_AT_high_pc \ > + "[lindex $result 0] + [lindex $result 1]" DW_FORM_addr > + } > + default { error "unknown macro attribute $attr_name" } > + } > + } > + > proc _handle_DW_TAG {tag_name {attrs {}} {children {}}} { > variable _abbrev_section > variable _abbrev_num > @@ -494,14 +605,19 @@ namespace eval Dwarf { > foreach attr $attrs { > set attr_name [_map_name [lindex $attr 0] _AT] > set attr_value [uplevel 2 [list subst [lindex $attr 1]]] > - if {[llength $attr] > 2} { > - set attr_form [lindex $attr 2] > + > + if { [string match "MACRO_AT_*" $attr_name] } { > + _handle_macro_attribute $attr_name $attr_value > } else { > - set attr_form [_guess_form $attr_value attr_value] > - } > - set attr_form [_map_name $attr_form _FORM] > + if {[llength $attr] > 2} { > + set attr_form [lindex $attr 2] > + } else { > + set attr_form [_guess_form $attr_value attr_value] > + } > + set attr_form [_map_name $attr_form _FORM] > > - _handle_attribute $attr_name $attr_value $attr_form > + _handle_attribute $attr_name $attr_value $attr_form > + } > } > > _defer_output $_abbrev_section { Hi. IWBN if one could add new macros simply by writing a new function. Can _handle_macro_attribute be rewritten such that MACRO_AT_{func,range} are themselves functions?