File Handle-user-supplied-sdt-probe-argument-templat... of Package systemtap

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File Handle-user-supplied-sdt-probe-argument-template.patch of Package systemtap (Revision a00edac39ca3e91b9b27abef774ed803)

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From ecab2afea46099b4e7dfd551462689224afdbe3a Mon Sep 17 00:00:00 2001
From: Stan Cox <scox@redhat.com>
Date: Wed, 1 Dec 2021 16:19:22 -0500
Subject: [PATCH] Handle user supplied sdt probe argument template

User supplied templates were erroneously removed by commit eaa15b047,
which complicated the template expansion. To do the above the
expansion of STAP_PROBE_ASM(provider, fooprobe,
STAP_PROBE_ASM_TEMPLATE(3)) adds an unused argument:
STAP_PROBE_ASM(provider, fooprobe, /*template expansion*/ "%[SDT..]..",
"use _SDT_ASM_TEMPLATE") A supplied template
STAP_PROBE_ASM(provider, fooprobe, "4@%rdx 8@%rax") is left alone.  If
the varargs has 2 args (the fake "use ..") then macro expansion
inserts the expanded string, otherwise "4@.." becomes an ascii op.
---
 includes/sys/sdt.h                    | 14 ++++++++++----
 testsuite/systemtap.base/sdt_casm.c   |  5 +++++
 testsuite/systemtap.base/sdt_casm.exp |  3 ++-
 testsuite/systemtap.base/sdt_casm.stp |  8 ++++++++
 4 files changed, 25 insertions(+), 5 deletions(-)

diff --git a/includes/sys/sdt.h b/includes/sys/sdt.h
index 28d236d91..24d5e01c3 100644
--- a/includes/sys/sdt.h
+++ b/includes/sys/sdt.h
@@ -290,7 +290,7 @@ __extension__ extern unsigned long long __sdt_unsp;
   _SDT_ASM_1(.purgem _SDT_TYPE_)					      \
   _SDT_ASM_1(.purgem _SDT_TYPE)
 
-#define _SDT_ASM_BODY(provider, name, pack_args, args)			      \
+#define _SDT_ASM_BODY(provider, name, pack_args, args, ...)		      \
   _SDT_DEF_MACROS							      \
   _SDT_ASM_1(990:	_SDT_NOP)					      \
   _SDT_ASM_3(		.pushsection .note.stapsdt,_SDT_ASM_AUTOGROUP,"note") \
@@ -417,9 +417,9 @@ __extension__ extern unsigned long long __sdt_unsp;
    counted, so we don't have to worry about the behavior of macros
    called without any arguments.  */
 
-#ifdef SDT_USE_VARIADIC
 #define _SDT_NARG(...) __SDT_NARG(__VA_ARGS__, 12,11,10,9,8,7,6,5,4,3,2,1,0)
 #define __SDT_NARG(_0,_1,_2,_3,_4,_5,_6,_7,_8,_9,_10,_11,_12, N, ...) N
+#ifdef SDT_USE_VARIADIC
 #define _SDT_PROBE_N(provider, name, N, ...) \
   _SDT_PROBE(provider, name, N, (__VA_ARGS__))
 #define STAP_PROBEV(provider, name, ...) \
@@ -468,9 +468,15 @@ __extension__ extern unsigned long long __sdt_unsp;
     Note that these can use operand templates like %0 or %[name],
     and likewise they must write %%reg for a literal operand of %reg.  */
 
+#define _SDT_ASM_BODY_1(p,n,...) _SDT_ASM_BODY(p,n,_SDT_ASM_SUBSTR,(__VA_ARGS__))
+#define _SDT_ASM_BODY_2(p,n,...) _SDT_ASM_BODY(p,n,/*_SDT_ASM_STRING */,__VA_ARGS__)
+#define _SDT_ASM_BODY_N2(p,n,no,...) _SDT_ASM_BODY_ ## no(p,n,__VA_ARGS__)
+#define _SDT_ASM_BODY_N1(p,n,no,...) _SDT_ASM_BODY_N2(p,n,no,__VA_ARGS__)
+#define _SDT_ASM_BODY_N(p,n,...) _SDT_ASM_BODY_N1(p,n,_SDT_NARG(0, __VA_ARGS__),__VA_ARGS__)
+
 #if __STDC_VERSION__ >= 199901L
 # define STAP_PROBE_ASM(provider, name, ...)		\
-  _SDT_ASM_BODY(provider, name, /*_SDT_ASM_STRING */, __VA_ARGS__)	\
+  _SDT_ASM_BODY_N(provider, name, __VA_ARGS__)					\
   _SDT_ASM_BASE
 # define STAP_PROBE_ASM_OPERANDS(n, ...) _SDT_ASM_OPERANDS_##n(__VA_ARGS__)
 #else
@@ -478,7 +484,7 @@ __extension__ extern unsigned long long __sdt_unsp;
   _SDT_ASM_BODY(provider, name, /* _SDT_ASM_STRING */, (args))	\
   _SDT_ASM_BASE
 #endif
-#define STAP_PROBE_ASM_TEMPLATE(n)	_SDT_ASM_TEMPLATE_##n
+#define STAP_PROBE_ASM_TEMPLATE(n) _SDT_ASM_TEMPLATE_##n,"use _SDT_ASM_TEMPLATE_"
 
 
 /* DTrace compatible macro names.  */
diff --git a/testsuite/systemtap.base/sdt_casm.c b/testsuite/systemtap.base/sdt_casm.c
index 1cff23c5f..9b357086c 100644
--- a/testsuite/systemtap.base/sdt_casm.c
+++ b/testsuite/systemtap.base/sdt_casm.c
@@ -3,6 +3,7 @@
 int main()
 {
     int x = 42;
+    int y = 43;
     __asm__ __volatile__ (
             STAP_PROBE_ASM(testsuite, probe0, STAP_PROBE_ASM_TEMPLATE(0))
             );
@@ -10,5 +11,9 @@ int main()
             STAP_PROBE_ASM(testsuite, probe1, STAP_PROBE_ASM_TEMPLATE(1))
             :: STAP_PROBE_ASM_OPERANDS(1, x)
             );
+    // Create a template to test explicit template support
+    __asm__ __volatile__ (
+			  STAP_PROBE_ASM(testsuite, probe2, -4@%[ARG1] -4@%[ARG2])
+			  :: [ARG1] "rm" (x), [ARG2] "rm" (y));
     return 0;
 }
diff --git a/testsuite/systemtap.base/sdt_casm.exp b/testsuite/systemtap.base/sdt_casm.exp
index 5791cb2b9..0cd1cb517 100644
--- a/testsuite/systemtap.base/sdt_casm.exp
+++ b/testsuite/systemtap.base/sdt_casm.exp
@@ -18,7 +18,8 @@ proc cleanup_handler { verbose } {
 
 set script $srcdir/$subdir/$test.stp
 set ::result_string {PASS: probe0
-PASS: probe1}
+PASS: probe1
+PASS: probe2}
 
 set asm_flags [sdt_includes]
 set asm_flags "$asm_flags additional_flags=-std=c99"
diff --git a/testsuite/systemtap.base/sdt_casm.stp b/testsuite/systemtap.base/sdt_casm.stp
index 4f2539c93..530a79175 100644
--- a/testsuite/systemtap.base/sdt_casm.stp
+++ b/testsuite/systemtap.base/sdt_casm.stp
@@ -10,3 +10,11 @@ probe process.mark("probe1")
     else
         printf("FAIL: %s (%d != 42)\n", $$name, $arg1)
 }
+
+probe process.mark("probe2") 
+{
+    if ($arg1 == 42 && $arg2 == 43)
+        printf("PASS: %s\n", $$name)
+    else
+        printf("FAIL: %s (%d/%d != 42/43)\n", $$name, $arg1, $arg2)
+}
-- 
2.35.0

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File Handle-user-supplied-sdt-probe-argument-template.patch of Package systemtap (Revision a00edac39ca3e91b9b27abef774ed803)

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