* [PATCH 1/3] add testcases for the linearization of calls
2017-12-21 0:06 [PATCH 0/3] fix function calls via pointers Luc Van Oostenryck
@ 2017-12-21 0:06 ` Luc Van Oostenryck
2017-12-21 0:06 ` [PATCH 2/3] simplify linearize_call_expression() Luc Van Oostenryck
2017-12-21 0:06 ` [PATCH 3/3] fix linearize (*fun)() Luc Van Oostenryck
2 siblings, 0 replies; 4+ messages in thread
From: Luc Van Oostenryck @ 2017-12-21 0:06 UTC (permalink / raw)
To: linux-sparse; +Cc: Luc Van Oostenryck
Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
---
validation/builtin-arith.c | 52 ++++++++++++++++++++++++++++
validation/function-pointer-type.c | 9 +++++
validation/linear/call-basic.c | 58 ++++++++++++++++++++++++++++++++
validation/linear/call-builtin.c | 14 ++++++++
validation/linear/call-casted-pointer.c | 32 ++++++++++++++++++
validation/linear/call-complex-pointer.c | 32 ++++++++++++++++++
validation/linear/call-direct.c | 14 ++++++++
validation/linear/call-indirect.c | 14 ++++++++
validation/linear/call-inline.c | 15 +++++++++
validation/optim/call-complex-pointer.c | 13 +++++++
validation/sizeof-builtin.c | 15 +++++++++
validation/sizeof-function.c | 50 +++++++++++++++++++++++++++
12 files changed, 318 insertions(+)
create mode 100644 validation/builtin-arith.c
create mode 100644 validation/function-pointer-type.c
create mode 100644 validation/linear/call-basic.c
create mode 100644 validation/linear/call-builtin.c
create mode 100644 validation/linear/call-casted-pointer.c
create mode 100644 validation/linear/call-complex-pointer.c
create mode 100644 validation/linear/call-direct.c
create mode 100644 validation/linear/call-indirect.c
create mode 100644 validation/linear/call-inline.c
create mode 100644 validation/optim/call-complex-pointer.c
create mode 100644 validation/sizeof-builtin.c
create mode 100644 validation/sizeof-function.c
diff --git a/validation/builtin-arith.c b/validation/builtin-arith.c
new file mode 100644
index 000000000..d08c93dab
--- /dev/null
+++ b/validation/builtin-arith.c
@@ -0,0 +1,52 @@
+
+
+void test(void (*fun)(void));
+void test(void (*fun)(void))
+{
+ typedef typeof(__builtin_trap) t; // OK
+ void (*f)(void);
+ int i;
+
+ f = __builtin_trap;
+ f = &__builtin_trap;
+ f = *__builtin_trap; // OK for GCC
+ f = __builtin_trap + 0;
+ f = __builtin_trap + 1;
+ f = __builtin_trap - 1;
+
+ // (void) __builtin_trap;
+ f = (void*) __builtin_trap;
+ f = (unsigned long) __builtin_trap;
+
+ i = !__builtin_trap;
+ i = (__builtin_trap > fun);
+ i = (__builtin_trap == fun);
+ i = (fun < __builtin_trap);
+ i = (fun == __builtin_trap);
+
+ __builtin_trap - fun;
+ fun - __builtin_trap;
+}
+
+/*
+ * check-name: builtin arithmetic
+ * check-command: sparse -Wno-decl $file
+ * check-known-to-fail
+ *
+ * check-error-start
+builtin-arith.c:10:xx: error: ...
+builtin-arith.c:11:xx: error: ...
+builtin-arith.c:13:xx: error: arithmetics on pointers to functions
+builtin-arith.c:14:xx: error: arithmetics on pointers to functions
+builtin-arith.c:15:xx: error: arithmetics on pointers to functions
+builtin-arith.c:18:xx: error: ...
+builtin-arith.c:19:xx: error: ...
+builtin-arith.c:21:xx: error: ...
+builtin-arith.c:22:xx: error: ...
+builtin-arith.c:23:xx: error: ...
+builtin-arith.c:24:xx: error: ...
+builtin-arith.c:25:xx: error: ...
+builtin-arith.c:27:24: error: subtraction of functions? Share your drugs
+builtin-arith.c:28:13: error: subtraction of functions? Share your drugs
+ * check-error-end
+ */
diff --git a/validation/function-pointer-type.c b/validation/function-pointer-type.c
new file mode 100644
index 000000000..8fd792b3b
--- /dev/null
+++ b/validation/function-pointer-type.c
@@ -0,0 +1,9 @@
+extern int fun(void);
+
+void fa(void) { int (*f)(void); f = &fun; }
+void f0(void) { int (*f)(void); f = fun; } // C99,C11 6.3.2.1p4
+
+/*
+ * check-name: type of function pointers
+ * check-command: sparse -Wno-decl $file
+ */
diff --git a/validation/linear/call-basic.c b/validation/linear/call-basic.c
new file mode 100644
index 000000000..235b443d2
--- /dev/null
+++ b/validation/linear/call-basic.c
@@ -0,0 +1,58 @@
+extern int fun(int a);
+
+int symbol(int a)
+{
+ fun(a);
+}
+
+int pointer0(int a, int (*fun)(int))
+{
+ fun(a);
+}
+
+int pointer1(int a, int (*fun)(int))
+{
+ (*fun)(a);
+}
+
+int builtin(int a)
+{
+ __builtin_popcount(a);
+}
+
+/*
+ * check-name: basic function calls
+ * check-command: test-linearize -Wno-decl $file
+ * check-known-to-fail
+ *
+ * check-output-start
+symbol:
+.L0:
+ <entry-point>
+ call.32 %r2 <- fun, %arg1
+ ret.32 %r2
+
+
+pointer0:
+.L2:
+ <entry-point>
+ call.32 %r5 <- %arg2, %arg1
+ ret.32 %r5
+
+
+pointer1:
+.L4:
+ <entry-point>
+ call.32 %r8 <- %arg2, %arg1
+ ret.32 %r8
+
+
+builtin:
+.L6:
+ <entry-point>
+ call.32 %r11 <- __builtin_popcount, %arg1
+ ret.32 %r11
+
+
+ * check-output-end
+ */
diff --git a/validation/linear/call-builtin.c b/validation/linear/call-builtin.c
new file mode 100644
index 000000000..af0148aa4
--- /dev/null
+++ b/validation/linear/call-builtin.c
@@ -0,0 +1,14 @@
+typedef unsigned int u32;
+
+u32 ff(u32 a) { return __builtin_popcount(a); }
+
+u32 f0(u32 a) { return (__builtin_popcount)(a); }
+
+/*
+ * check-name: builtin calls
+ * check-command: test-linearize -Wno-decl $file
+ *
+ * check-output-ignore
+ * check-output-excludes: load
+ * check-output-pattern(2): call\..*__builtin_.*, %arg1
+ */
diff --git a/validation/linear/call-casted-pointer.c b/validation/linear/call-casted-pointer.c
new file mode 100644
index 000000000..e66f69990
--- /dev/null
+++ b/validation/linear/call-casted-pointer.c
@@ -0,0 +1,32 @@
+typedef int (*fun_t)(void*);
+
+int foo(void *a, void *fun)
+{
+ return ((fun_t)fun)(a);
+}
+
+int bar(void *a, void *fun)
+{
+ return ((int (*)(void *))fun)(a);
+}
+
+int qux(void *a, void *fun)
+{
+ return (*(fun_t)fun)(a);
+}
+
+int quz(void *a, void *fun)
+{
+ return (*(int (*)(void *))fun)(a);
+}
+
+/*
+ * check-name: call via casted function pointer
+ * check-command: test-linearize -Wno-decl $file
+ * check-known-to-fail
+ *
+ * check-output-ignore
+ * check-output-excludes: load
+ * check-output-pattern(4): ptrcast\..* %arg2
+ * check-output-pattern(4): call\..* %arg1
+ */
diff --git a/validation/linear/call-complex-pointer.c b/validation/linear/call-complex-pointer.c
new file mode 100644
index 000000000..d95e18057
--- /dev/null
+++ b/validation/linear/call-complex-pointer.c
@@ -0,0 +1,32 @@
+int foo(int p, int (*f0)(int), int (*f1)(int), int arg)
+{
+ return (p ? f0 : f1)(arg);
+}
+
+/*
+ * check-name: call-complex-pointer
+ * check-command: test-linearize -Wno-decl $file
+ *
+ * check-output-start
+foo:
+.L0:
+ <entry-point>
+ cbr %arg1, .L2, .L3
+
+.L2:
+ phisrc.64 %phi1 <- %arg2
+ br .L4
+
+.L3:
+ ptrcast.64 %r5 <- (64) %arg3
+ phisrc.64 %phi2 <- %r5
+ br .L4
+
+.L4:
+ phi.64 %r6 <- %phi1, %phi2
+ call.32 %r7 <- %r6, %arg4
+ ret.32 %r7
+
+
+ * check-output-end
+ */
diff --git a/validation/linear/call-direct.c b/validation/linear/call-direct.c
new file mode 100644
index 000000000..78321ab02
--- /dev/null
+++ b/validation/linear/call-direct.c
@@ -0,0 +1,14 @@
+extern int fun(void);
+
+int ff(void) { return fun(); }
+
+int f0(void) { return (fun)(); }
+
+/*
+ * check-name: direct calls
+ * check-command: test-linearize -Wno-decl $file
+ *
+ * check-output-ignore
+ * check-output-excludes: load
+ * check-output-pattern(2): call\..* fun
+ */
diff --git a/validation/linear/call-indirect.c b/validation/linear/call-indirect.c
new file mode 100644
index 000000000..8ab78676b
--- /dev/null
+++ b/validation/linear/call-indirect.c
@@ -0,0 +1,14 @@
+int gg(int (*fun)(void)) { return fun(); }
+
+int g0(int (*fun)(void)) { return (fun)(); }
+int g1(int (*fun)(void)) { return (*fun)(); } // C99,C11 6.5.3.2p4
+
+/*
+ * check-name: indirect calls
+ * check-command: test-linearize -Wno-decl $file
+ * check-known-to-fail
+ *
+ * check-output-ignore
+ * check-output-excludes: load
+ * check-output-pattern(3): call\..* %arg1
+ */
diff --git a/validation/linear/call-inline.c b/validation/linear/call-inline.c
new file mode 100644
index 000000000..32f32461c
--- /dev/null
+++ b/validation/linear/call-inline.c
@@ -0,0 +1,15 @@
+static inline int fun(void) { return 42; }
+
+int fi(void) { return fun(); }
+
+int i0(void) { return (fun)(); }
+
+/*
+ * check-name: inline calls
+ * check-command: test-linearize -Wno-decl $file
+ *
+ * check-output-ignore
+ * check-output-excludes: load
+ * check-output-excludes: call
+ * check-output-pattern(2): ret\..* \\$42
+ */
diff --git a/validation/optim/call-complex-pointer.c b/validation/optim/call-complex-pointer.c
new file mode 100644
index 000000000..6cfeb6abd
--- /dev/null
+++ b/validation/optim/call-complex-pointer.c
@@ -0,0 +1,13 @@
+int foo(int p, int (*f0)(int), int (*f1)(int), int arg)
+{
+ return (p ? f0 : f1)(arg);
+}
+/*
+ * check-name: call-complex-pointer
+ * check-command: test-linearize -Wno-decl $file
+ * check-known-to-fail
+ *
+ * check-output-ignore
+ * check-output-excludes: ptrcast\.
+ * check-output-contains: select\.
+ */
diff --git a/validation/sizeof-builtin.c b/validation/sizeof-builtin.c
new file mode 100644
index 000000000..7123e4deb
--- /dev/null
+++ b/validation/sizeof-builtin.c
@@ -0,0 +1,15 @@
+int test(void);
+int test(void)
+{
+ return sizeof &__builtin_trap;
+}
+
+/*
+ * check-name: sizeof-builtin
+ * check-command: sparse -Wno-decl $file
+ * check-known-to-fail
+ *
+ * check-error-start
+sizeof-function.c:4:16: error: expression using addressof on a builtin function
+ * check-error-end
+ */
diff --git a/validation/sizeof-function.c b/validation/sizeof-function.c
new file mode 100644
index 000000000..20c795e94
--- /dev/null
+++ b/validation/sizeof-function.c
@@ -0,0 +1,50 @@
+extern int fun(void);
+extern int (*ptr)(void);
+
+static inline int inl(int *a)
+{
+ return *a + 1;
+}
+
+
+int test(void);
+int test(void)
+{
+ unsigned int s = 0;
+
+ // OK
+ s += sizeof &fun;
+ s += sizeof ptr;
+ s += sizeof &ptr;
+ s += sizeof &inl;
+
+ // KO
+ s += sizeof fun;
+ s += sizeof *fun;
+
+ s += sizeof *ptr;
+
+ s += sizeof inl;
+ s += sizeof *inl;
+
+ s += sizeof __builtin_trap;
+ s += sizeof *__builtin_trap;
+
+ return s;
+}
+
+/*
+ * check-name: sizeof-function
+ * check-command: sparse -Wno-decl $file
+ * check-known-to-fail
+ *
+ * check-error-start
+sizeof-function.c:22:14: warning: expression using sizeof on a function
+sizeof-function.c:23:14: warning: expression using sizeof on a function
+sizeof-function.c:25:14: warning: expression using sizeof on a function
+sizeof-function.c:27:14: warning: expression using sizeof on a function
+sizeof-function.c:28:14: warning: expression using sizeof on a function
+sizeof-function.c:30:14: warning: expression using sizeof on a function
+sizeof-function.c:31:14: warning: expression using sizeof on a function
+ * check-error-end
+ */
--
2.15.0
^ permalink raw reply related [flat|nested] 4+ messages in thread* [PATCH 3/3] fix linearize (*fun)()
2017-12-21 0:06 [PATCH 0/3] fix function calls via pointers Luc Van Oostenryck
2017-12-21 0:06 ` [PATCH 1/3] add testcases for the linearization of calls Luc Van Oostenryck
2017-12-21 0:06 ` [PATCH 2/3] simplify linearize_call_expression() Luc Van Oostenryck
@ 2017-12-21 0:06 ` Luc Van Oostenryck
2 siblings, 0 replies; 4+ messages in thread
From: Luc Van Oostenryck @ 2017-12-21 0:06 UTC (permalink / raw)
To: linux-sparse; +Cc: Luc Van Oostenryck
A function call via a function pointer can be written like:
fp(), (fp)() or (*fp)()
In the latter case the dereference is unneeded but legal and
idiomatic.
However, the linearization doesn't handle this unneeded deref
and leads to the generation of a load of the pointer:
int foo(int a, int (*fun)(int))
{
(*fun)(a);
}
gives something like:
foo:
load %r2 <- 0[%arg2]
call.32 %r3 <- %r2, %arg1
ret.32 %r3
This happens because, at linearization, the deref is dropped
but only if the sub-expression is a symbol and the test for
node is not done.
Fix this by using is_func_type() to test the type of all call
expressions.
Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
---
linearize.c | 10 +++-------
validation/linear/call-basic.c | 1 -
validation/linear/call-casted-pointer.c | 1 -
validation/linear/call-indirect.c | 1 -
4 files changed, 3 insertions(+), 10 deletions(-)
diff --git a/linearize.c b/linearize.c
index 7ad348c00..2e146de7a 100644
--- a/linearize.c
+++ b/linearize.c
@@ -1291,13 +1291,9 @@ static pseudo_t linearize_call_expression(struct entrypoint *ep, struct expressi
add_symbol(&insn->fntypes, arg->ctype);
} END_FOR_EACH_PTR(arg);
- if (fn->type == EXPR_PREOP) {
- if (fn->unop->type == EXPR_SYMBOL) {
- struct symbol *sym = fn->unop->symbol;
- if (sym->ctype.base_type->type == SYM_FN)
- fn = fn->unop;
- }
- }
+ if (fn->type == EXPR_PREOP && fn->op == '*' && is_func_type(fn->ctype))
+ fn = fn->unop;
+
if (fn->type == EXPR_SYMBOL) {
call = symbol_pseudo(ep, fn->symbol);
} else {
diff --git a/validation/linear/call-basic.c b/validation/linear/call-basic.c
index 235b443d2..60517e2e3 100644
--- a/validation/linear/call-basic.c
+++ b/validation/linear/call-basic.c
@@ -23,7 +23,6 @@ int builtin(int a)
/*
* check-name: basic function calls
* check-command: test-linearize -Wno-decl $file
- * check-known-to-fail
*
* check-output-start
symbol:
diff --git a/validation/linear/call-casted-pointer.c b/validation/linear/call-casted-pointer.c
index e66f69990..610d67482 100644
--- a/validation/linear/call-casted-pointer.c
+++ b/validation/linear/call-casted-pointer.c
@@ -23,7 +23,6 @@ int quz(void *a, void *fun)
/*
* check-name: call via casted function pointer
* check-command: test-linearize -Wno-decl $file
- * check-known-to-fail
*
* check-output-ignore
* check-output-excludes: load
diff --git a/validation/linear/call-indirect.c b/validation/linear/call-indirect.c
index 8ab78676b..f5f2adaf1 100644
--- a/validation/linear/call-indirect.c
+++ b/validation/linear/call-indirect.c
@@ -6,7 +6,6 @@ int g1(int (*fun)(void)) { return (*fun)(); } // C99,C11 6.5.3.2p4
/*
* check-name: indirect calls
* check-command: test-linearize -Wno-decl $file
- * check-known-to-fail
*
* check-output-ignore
* check-output-excludes: load
--
2.15.0
^ permalink raw reply related [flat|nested] 4+ messages in thread