* demangler: Templated lambda demangling
@ 2022-11-10 23:25 Nathan Sidwell
0 siblings, 0 replies; only message in thread
From: Nathan Sidwell @ 2022-11-10 23:25 UTC (permalink / raw)
To: GCC Patches
[-- Attachment #1: Type: text/plain, Size: 716 bytes --]
Templated lambdas have a template-head, which is part of their
signature. GCC ABI 18 mangles that into the lambda name. This adds
support to the demangler. We have to introduce artificial template
parameter names, as we need to refer to them from later components of
the lambda signature. We use $T:n, $N:n and $TT:n for type, non-type
and template parameters. Non-type parameter names are not shown in
the strictly correct location -- for instance 'int (&NT) ()' would be
shown as 'int (&) $N:n'. That's unfortunate, but an orthogonal issue.
The 'is_lambda_arg' field is now repurposed as indicating the number
of explicit template parameters (1-based).
I'll commit in a few days.
nathan
--
Nathan Sidwell
[-- Attachment #2: 0001-demangler-Templated-lambda-demangling.patch --]
[-- Type: text/x-patch, Size: 16411 bytes --]
From b7f0ba90011b8c9cae7b7278463f609ba21cd44b Mon Sep 17 00:00:00 2001
From: Nathan Sidwell <nathan@acm.org>
Date: Mon, 7 Nov 2022 11:24:14 -0500
Subject: [PATCH] demangler: Templated lambda demangling
Templated lambdas have a template-head, which is part of their
signature. GCC ABI 18 mangles that into the lambda name. This adds
support to the demangler. We have to introduce artificial template
parameter names, as we need to refer to them from later components of
the lambda signature. We use $T:n, $N:n and $TT:n for type, non-type
and template parameters. Non-type parameter names are not shown in
the strictly correct location -- for instance 'int (&NT) ()' would be
shown as 'int (&) $N:n'. That's unfortunate, but an orthogonal issue.
The 'is_lambda_arg' field is now repurposed as indicating the number
of explicit template parameters (1-based).
include/
* demangle.h (enum demangle_component_type): Add
DEMANGLE_COMPONENT_TEMPLATE_HEAD,
DEMANGLE_COMPONENT_TEMPLATE_TYPE_PARM,
DEMANGLE_COMPONENT_TEMPLATE_NON_TYPE_PARM,
DEMANGLE_COMPONENT_TEMPLATE_TEMPLATE_PARM,
DEMANGLE_COMPONENT_TEMPLATE_PACK_PARM.
libiberty/
* cp-demangle.c (struct d_print_info): Rename is_lambda_arg to
lambda_tpl_parms. Augment semantics.
(d_make_comp): Add checks for new components.
(d_template_parm, d_template_head): New.
(d_lambda): Add templated lambda support.
(d_print_init): Adjust.
(d_print_lambda_parm_name): New.
(d_print_comp_inner): Support templated lambdas,
* testsuite/demangle-expected: Add testcases.
---
include/demangle.h | 6 +
libiberty/cp-demangle.c | 260 +++++++++++++++++++++++---
libiberty/testsuite/demangle-expected | 53 ++++++
3 files changed, 295 insertions(+), 24 deletions(-)
diff --git a/include/demangle.h b/include/demangle.h
index 81d4353a86f..66637ebdc16 100644
--- a/include/demangle.h
+++ b/include/demangle.h
@@ -458,6 +458,12 @@ enum demangle_component_type
DEMANGLE_COMPONENT_MODULE_ENTITY,
DEMANGLE_COMPONENT_MODULE_INIT,
+ DEMANGLE_COMPONENT_TEMPLATE_HEAD,
+ DEMANGLE_COMPONENT_TEMPLATE_TYPE_PARM,
+ DEMANGLE_COMPONENT_TEMPLATE_NON_TYPE_PARM,
+ DEMANGLE_COMPONENT_TEMPLATE_TEMPLATE_PARM,
+ DEMANGLE_COMPONENT_TEMPLATE_PACK_PARM,
+
/* A builtin type with argument. This holds the builtin type
information. */
DEMANGLE_COMPONENT_EXTENDED_BUILTIN_TYPE
diff --git a/libiberty/cp-demangle.c b/libiberty/cp-demangle.c
index 8413dcdc785..ad533f6085e 100644
--- a/libiberty/cp-demangle.c
+++ b/libiberty/cp-demangle.c
@@ -347,9 +347,9 @@ struct d_print_info
/* Number of times d_print_comp was recursively called. Should not
be bigger than MAX_RECURSION_COUNT. */
int recursion;
- /* Non-zero if we're printing a lambda argument. A template
- parameter reference actually means 'auto', a pack expansion means T... */
- int is_lambda_arg;
+ /* 1 more than the number of explicit template parms of a lambda. Template
+ parm references >= are actually 'auto'. */
+ int lambda_tpl_parms;
/* The current index into any template argument packs we are using
for printing, or -1 to print the whole pack. */
int pack_index;
@@ -491,6 +491,10 @@ static struct demangle_component *d_local_name (struct d_info *);
static int d_discriminator (struct d_info *);
+static struct demangle_component *d_template_parm (struct d_info *, int *bad);
+
+static struct demangle_component *d_template_head (struct d_info *, int *bad);
+
static struct demangle_component *d_lambda (struct d_info *);
static struct demangle_component *d_unnamed_type (struct d_info *);
@@ -1028,6 +1032,10 @@ d_make_comp (struct d_info *di, enum demangle_component_type type,
case DEMANGLE_COMPONENT_TPARM_OBJ:
case DEMANGLE_COMPONENT_STRUCTURED_BINDING:
case DEMANGLE_COMPONENT_MODULE_INIT:
+ case DEMANGLE_COMPONENT_TEMPLATE_HEAD:
+ case DEMANGLE_COMPONENT_TEMPLATE_NON_TYPE_PARM:
+ case DEMANGLE_COMPONENT_TEMPLATE_TEMPLATE_PARM:
+ case DEMANGLE_COMPONENT_TEMPLATE_PACK_PARM:
if (left == NULL)
return NULL;
break;
@@ -1050,6 +1058,7 @@ d_make_comp (struct d_info *di, enum demangle_component_type type,
case DEMANGLE_COMPONENT_CONST:
case DEMANGLE_COMPONENT_ARGLIST:
case DEMANGLE_COMPONENT_TEMPLATE_ARGLIST:
+ case DEMANGLE_COMPONENT_TEMPLATE_TYPE_PARM:
FNQUAL_COMPONENT_CASE:
break;
@@ -3877,32 +3886,120 @@ d_discriminator (struct d_info *di)
return 1;
}
-/* <closure-type-name> ::= Ul <lambda-sig> E [ <nonnegative number> ] _ */
+/* <template-parm> ::= Ty
+ ::= Tn <type>
+ ::= Tt <template-head> E
+ ::= Tp <template-parm> */
+
+static struct demangle_component *
+d_template_parm (struct d_info *di, int *bad)
+{
+ if (d_peek_char (di) != 'T')
+ return NULL;
+
+ struct demangle_component *op;
+ enum demangle_component_type kind;
+ switch (d_peek_next_char (di))
+ {
+ default:
+ return NULL;
+
+ case 'p': /* Pack */
+ d_advance (di, 2);
+ op = d_template_parm (di, bad);
+ kind = DEMANGLE_COMPONENT_TEMPLATE_PACK_PARM;
+ if (!op)
+ {
+ *bad = 1;
+ return NULL;
+ }
+ break;
+
+ case 'y': /* Typename */
+ d_advance (di, 2);
+ op = NULL;
+ kind = DEMANGLE_COMPONENT_TEMPLATE_TYPE_PARM;
+ break;
+
+ case 'n': /* Non-Type */
+ d_advance (di, 2);
+ op = cplus_demangle_type (di);
+ kind = DEMANGLE_COMPONENT_TEMPLATE_NON_TYPE_PARM;
+ if (!op)
+ {
+ *bad = 1;
+ return NULL;
+ }
+ break;
+
+ case 't': /* Template */
+ d_advance (di, 2);
+ op = d_template_head (di, bad);
+ kind = DEMANGLE_COMPONENT_TEMPLATE_TEMPLATE_PARM;
+ if (!op || !d_check_char (di, 'E'))
+ {
+ *bad = 1;
+ return NULL;
+ }
+ }
+
+ return d_make_comp (di, kind, op, NULL);
+}
+
+/* <template-head> ::= <template-head>? <template-parm> */
+
+static struct demangle_component *
+d_template_head (struct d_info *di, int *bad)
+{
+ struct demangle_component *res = NULL, **slot = &res;
+ struct demangle_component *op;
+
+ while ((op = d_template_parm (di, bad)))
+ {
+ *slot = op;
+ slot = &d_right (op);
+ }
+
+ /* Wrap it in a template head, to make concatenating with any parm list, and
+ printing simpler. */
+ if (res)
+ res = d_make_comp (di, DEMANGLE_COMPONENT_TEMPLATE_HEAD, res, NULL);
+
+ return res;
+}
+
+/* <closure-type-name> ::= Ul <template-head>? <lambda-sig> E [ <nonnegative number> ] _ */
static struct demangle_component *
d_lambda (struct d_info *di)
{
- struct demangle_component *tl;
- struct demangle_component *ret;
- int num;
-
if (! d_check_char (di, 'U'))
return NULL;
if (! d_check_char (di, 'l'))
return NULL;
- tl = d_parmlist (di);
+ int bad = 0;
+ struct demangle_component *head = d_template_head (di, &bad);
+ if (bad)
+ return NULL;
+
+ struct demangle_component *tl = d_parmlist (di);
if (tl == NULL)
return NULL;
+ if (head)
+ {
+ d_right (head) = tl;
+ tl = head;
+ }
if (! d_check_char (di, 'E'))
return NULL;
- num = d_compact_number (di);
+ int num = d_compact_number (di);
if (num < 0)
return NULL;
- ret = d_make_empty (di);
+ struct demangle_component *ret = d_make_empty (di);
if (ret)
{
ret->type = DEMANGLE_COMPONENT_LAMBDA;
@@ -4254,6 +4351,11 @@ d_count_templates_scopes (struct d_print_info *dpi,
case DEMANGLE_COMPONENT_MODULE_PARTITION:
case DEMANGLE_COMPONENT_MODULE_INIT:
case DEMANGLE_COMPONENT_FIXED_TYPE:
+ case DEMANGLE_COMPONENT_TEMPLATE_HEAD:
+ case DEMANGLE_COMPONENT_TEMPLATE_TYPE_PARM:
+ case DEMANGLE_COMPONENT_TEMPLATE_NON_TYPE_PARM:
+ case DEMANGLE_COMPONENT_TEMPLATE_TEMPLATE_PARM:
+ case DEMANGLE_COMPONENT_TEMPLATE_PACK_PARM:
break;
case DEMANGLE_COMPONENT_TEMPLATE:
@@ -4384,7 +4486,7 @@ d_print_init (struct d_print_info *dpi, demangle_callbackref callback,
dpi->demangle_failure = 0;
dpi->recursion = 0;
- dpi->is_lambda_arg = 0;
+ dpi->lambda_tpl_parms = 0;
dpi->component_stack = NULL;
@@ -4881,6 +4983,33 @@ d_maybe_print_designated_init (struct d_print_info *dpi, int options,
return 1;
}
+static void
+d_print_lambda_parm_name (struct d_print_info *dpi, int type, unsigned index)
+{
+ const char *str;
+ switch (type)
+ {
+ default:
+ dpi->demangle_failure = 1;
+ str = "";
+ break;
+
+ case DEMANGLE_COMPONENT_TEMPLATE_TYPE_PARM:
+ str = "$T";
+ break;
+
+ case DEMANGLE_COMPONENT_TEMPLATE_NON_TYPE_PARM:
+ str = "$N";
+ break;
+
+ case DEMANGLE_COMPONENT_TEMPLATE_TEMPLATE_PARM:
+ str = "$TT";
+ break;
+ }
+ d_append_string (dpi, str);
+ d_append_num (dpi, index);
+}
+
/* Subroutine to handle components. */
static void
@@ -5135,7 +5264,21 @@ d_print_comp_inner (struct d_print_info *dpi, int options,
}
case DEMANGLE_COMPONENT_TEMPLATE_PARAM:
- if (dpi->is_lambda_arg)
+ if (dpi->lambda_tpl_parms > dc->u.s_number.number + 1)
+ {
+ const struct demangle_component *a
+ = d_left (dpi->templates->template_decl);
+ unsigned c;
+ for (c = dc->u.s_number.number; a && c; c--)
+ a = d_right (a);
+ if (a && a->type == DEMANGLE_COMPONENT_TEMPLATE_PACK_PARM)
+ a = d_left (a);
+ if (!a)
+ dpi->demangle_failure = 1;
+ else
+ d_print_lambda_parm_name (dpi, a->type, dc->u.s_number.number);
+ }
+ else if (dpi->lambda_tpl_parms)
{
/* Show the template parm index, as that's how g++ displays
these, and future proofs us against potential
@@ -5316,7 +5459,7 @@ d_print_comp_inner (struct d_print_info *dpi, int options,
{
/* Handle reference smashing: & + && = &. */
struct demangle_component *sub = d_left (dc);
- if (!dpi->is_lambda_arg
+ if (!dpi->lambda_tpl_parms
&& sub->type == DEMANGLE_COMPONENT_TEMPLATE_PARAM)
{
struct d_saved_scope *scope = d_get_saved_scope (dpi, sub);
@@ -5942,7 +6085,7 @@ d_print_comp_inner (struct d_print_info *dpi, int options,
{
struct demangle_component *a = NULL;
- if (!dpi->is_lambda_arg)
+ if (!dpi->lambda_tpl_parms)
a = d_find_pack (dpi, d_left (dc));
if (a == NULL)
{
@@ -5994,15 +6137,50 @@ d_print_comp_inner (struct d_print_info *dpi, int options,
return;
case DEMANGLE_COMPONENT_LAMBDA:
- d_append_string (dpi, "{lambda(");
- /* Generic lambda auto parms are mangled as the template type
- parm they are. */
- dpi->is_lambda_arg++;
- d_print_comp (dpi, options, dc->u.s_unary_num.sub);
- dpi->is_lambda_arg--;
- d_append_string (dpi, ")#");
- d_append_num (dpi, dc->u.s_unary_num.num + 1);
- d_append_char (dpi, '}');
+ {
+ d_append_string (dpi, "{lambda");
+ struct demangle_component *parms = dc->u.s_unary_num.sub;
+ struct d_print_template dpt;
+ /* Generic lambda auto parms are mangled as the (synthedic) template
+ type parm they are. We need to tell the printer that (a) we're in
+ a lambda, and (b) the number of synthetic parms. */
+ int saved_tpl_parms = dpi->lambda_tpl_parms;
+ dpi->lambda_tpl_parms = 0;
+ /* Hang any lambda head as-if template args. */
+ dpt.template_decl = NULL;
+ dpt.next = dpi->templates;
+ dpi->templates = &dpt;
+ if (parms && parms->type == DEMANGLE_COMPONENT_TEMPLATE_HEAD)
+ {
+ dpt.template_decl = parms;
+
+ d_append_char (dpi, '<');
+ struct demangle_component *parm;
+ for (parm = d_left (parms); parm; parm = d_right (parm))
+ {
+ if (dpi->lambda_tpl_parms++)
+ d_append_string (dpi, ", ");
+ d_print_comp (dpi, options, parm);
+ d_append_char (dpi, ' ');
+ if (parm->type == DEMANGLE_COMPONENT_TEMPLATE_PACK_PARM)
+ parm = d_left (parm);
+ d_print_lambda_parm_name (dpi, parm->type,
+ dpi->lambda_tpl_parms - 1);
+ }
+ d_append_char (dpi, '>');
+
+ parms = d_right (parms);
+ }
+ dpi->lambda_tpl_parms++;
+
+ d_append_char (dpi, '(');
+ d_print_comp (dpi, options, parms);
+ dpi->lambda_tpl_parms = saved_tpl_parms;
+ dpi->templates = dpt.next;
+ d_append_string (dpi, ")#");
+ d_append_num (dpi, dc->u.s_unary_num.num + 1);
+ d_append_char (dpi, '}');
+ }
return;
case DEMANGLE_COMPONENT_UNNAMED_TYPE:
@@ -6018,6 +6196,40 @@ d_print_comp_inner (struct d_print_info *dpi, int options,
d_append_char (dpi, ']');
return;
+ case DEMANGLE_COMPONENT_TEMPLATE_HEAD:
+ {
+ d_append_char (dpi, '<');
+ int count = 0;
+ struct demangle_component *parm;
+ for (parm = d_left (dc); parm; parm = d_right (parm))
+ {
+ if (count++)
+ d_append_string (dpi, ", ");
+ d_print_comp (dpi, options, parm);
+ }
+ d_append_char (dpi, '>');
+ }
+ return;
+
+ case DEMANGLE_COMPONENT_TEMPLATE_TYPE_PARM:
+ d_append_string (dpi, "typename");
+ return;
+
+ case DEMANGLE_COMPONENT_TEMPLATE_NON_TYPE_PARM:
+ d_print_comp (dpi, options, d_left (dc));
+ return;
+
+ case DEMANGLE_COMPONENT_TEMPLATE_TEMPLATE_PARM:
+ d_append_string (dpi, "template");
+ d_print_comp (dpi, options, d_left (dc));
+ d_append_string (dpi, " class");
+ return;
+
+ case DEMANGLE_COMPONENT_TEMPLATE_PACK_PARM:
+ d_print_comp (dpi, options, d_left (dc));
+ d_append_string (dpi, "...");
+ return;
+
default:
d_print_error (dpi);
return;
diff --git a/libiberty/testsuite/demangle-expected b/libiberty/testsuite/demangle-expected
index ee8fdfdd9cf..d9bc7ed4b1f 100644
--- a/libiberty/testsuite/demangle-expected
+++ b/libiberty/testsuite/demangle-expected
@@ -1606,3 +1606,56 @@ int foo<q::{lambda()#1}, q::{lambda()#2}>(q::{lambda()#1}&&, q::{lambda()#2}&&)
_ZNK2L1MUlDpT_E_clIJiPiEEEvS1_
void L1::{lambda((auto:1)...)#1}::operator()<int, int*>(int, int*) const
+_ZZN1XIfLj0EE2FnEvENKUlTyfT_E_clIiEEDafS1_
+auto X<float, 0u>::Fn()::{lambda<typename $T0>(float, $T0)#1}::operator()<int>(float, int) const
+
+_ZZN1XIfLj0EE2FnEvENKUlTyT_E_clIiEEDaS1_
+auto X<float, 0u>::Fn()::{lambda<typename $T0>($T0)#1}::operator()<int>(int) const
+
+_ZZN1XIfLj1EE2FnEvENKUlTyfT_E_clIiEEDafS1_
+auto X<float, 1u>::Fn()::{lambda<typename $T0>(float, $T0)#1}::operator()<int>(float, int) const
+
+_ZZN1XIfLj1EE2FnEvENKUlTyT_E_clIiEEDaS1_
+auto X<float, 1u>::Fn()::{lambda<typename $T0>($T0)#1}::operator()<int>(int) const
+
+_ZZN1XIiLj0EE2FnEvENKUlTyiT_E_clIiEEDaiS1_
+auto X<int, 0u>::Fn()::{lambda<typename $T0>(int, $T0)#1}::operator()<int>(int, int) const
+
+_ZZN1XIiLj0EE2FnEvENKUlTyT_E_clIiEEDaS1_
+auto X<int, 0u>::Fn()::{lambda<typename $T0>($T0)#1}::operator()<int>(int) const
+
+_ZNK10l_tpl_autoMUlTyT_T0_E_clIiiEEDaS0_S1_
+auto l_tpl_auto::{lambda<typename $T0>($T0, auto:2)#1}::operator()<int, int>(int, int) const
+
+_ZNK12l_tpl_nt_aryMUlTniRAT__iE_clILi2EEEDaS1_
+auto l_tpl_nt_ary::{lambda<int $N0>(int (&) [$N0])#1}::operator()<2>(int (&) [2]) const
+
+_ZNK13l_tpl_nt_autoMUlTnDavE_clILi0EEEDav
+auto l_tpl_nt_auto::{lambda<auto $N0>()#1}::operator()<0>() const
+
+_ZNK9l_tpl_tplMUlTtTyTnjER3TPLIT_EE_clI1UEEDaS3_
+auto l_tpl_tpl::{lambda<template<typename, unsigned int> class $TT0>(TPL<$TT0>&)#1}::operator()<U>(TPL<U>&) const
+
+_ZNK13l_tpl_tpl_tplMUlTtTtTyTnjEER6TPLTPLIT_EE_clI3TPLEEDaS3_
+auto l_tpl_tpl_tpl::{lambda<template<template<typename, unsigned int> class> class $TT0>(TPLTPL<$TT0>&)#1}::operator()<TPL>(TPLTPL<TPL>&) const
+
+_ZNK5l_varMUlTpTyDpT_E_clIJiiiEEEDaS1_
+auto l_var::{lambda<typename... $T0>(($T0)...)#1}::operator()<int, int, int>(int, int, int) const
+
+_ZNK6l_var2MUlTpTniDpRAT__iE_clIJLi2ELi2EEEEDaS2_
+auto l_var2::{lambda<int... $N0>((int (&) [$N0])...)#1}::operator()<2, 2>(int (&) [2], int (&) [2]) const
+
+_ZNK6l_var3MUlTtTpTniETpTniRT_IJXspT0_EEEE_clI1XJLi1ELi2ELi3EEEEDaS2_
+auto l_var3::{lambda<template<int...> class $TT0, int... $N1>($TT0<($N1)...>&)#1}::operator()<X, 1, 2, 3>(X<1, 2, 3>&) const
+
+_ZNK6l_var4MUlTpTtTyTnjER1YIJDpT_EEE_clIJ1US7_EEEDaS4_
+auto l_var4::{lambda<template<typename, unsigned int> class... $TT0>(Y<($TT0)...>&)#1}::operator()<U, U>(Y<U, U>&) const
+
+_ZZ2FnILi1EEvvENKUlTyT_E_clIiEEDaS0_
+auto Fn<1>()::{lambda<typename $T0>($T0)#1}::operator()<int>(int) const
+
+_ZZ1fvENKUlTyP1XIT_EPS_IiEE_clIcEEDaS2_S4_
+auto f()::{lambda<typename $T0>(X<$T0>*, X<int>*)#1}::operator()<char>(X<char>*, X<int>*) const
+
+_ZZN1XIiE1FEvENKUliE_clEi
+X<int>::F()::{lambda(int)#1}::operator()(int) const
--
2.38.1
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