Hack in basic assertions

Signed-off-by: Will Deacon <will.deacon@arm.com>

5 files changed, 26 insertions, 7 deletions

diff --git a/Makefile b/Makefile
index efee9a1..aeaab39 100644
--- a/Makefile
+++ b/Makefile
@@ -2,8 +2,8 @@ CC=aarch64-linux-gnu-gcc
 CFLAGS=-Wall -O2 -fno-strict-aliasing -g -ffreestanding
 LDFLAGS=-static -nostdlib
 TARGET=qrwlock
-HDRS= kernel.h compiler.h rmem.h
-OBJS= main.o qrwlock.o
+HDRS=kernel.h compiler.h rmem.h
+OBJS=main.o qrwlock.o
 
 $(TARGET) : $(OBJS) $(HDRS)
 all: $(TARGET)
diff --git a/compiler.h b/compiler.h
index b188726..8677fa8 100644
--- a/compiler.h
+++ b/compiler.h
@@ -1,6 +1,7 @@
 #ifndef __COMPILER_H
 #define __COMPILER_H
 
+#define barrier()	asm volatile("" ::: "memory")
 #define __branch_check__(x, expect, is_constant) ({			\
 			int ______r;					\
 			______r = __builtin_expect(!!(x), expect);	\
@@ -14,5 +15,6 @@
 #define __always_inline	inline __attribute__((always_inline))
 #define noinline	__attribute__((noinline))
 #define __noreturn	__attribute__((noreturn))
+#define _THIS_IP_	({ __label__ __here; __here: (unsigned long)&&__here; })
 
 #endif /* __COMPILER_H */
diff --git a/kernel.h b/kernel.h
index afecbaf..1455a91 100644
--- a/kernel.h
+++ b/kernel.h
@@ -8,7 +8,10 @@
 #include "compiler.h"
 #include "rmem.h"
 
-#define _abort	__rmem_stop
+/* Different ways to exit the model */
+#define assert(cond)	({ if (!(cond)) __rmem_stop(_THIS_IP_); })
+#define abort()		__rmem_stop(-1)
+#define exit()		__rmem_stop(0)
 
 /* Type definitions */
 typedef unsigned char		u8;
@@ -60,7 +63,7 @@ typedef struct qrwlock {
 	case 4: *(u32 *)res = *(volatile u32 *)p; break;		\
 	case 8: *(u64 *)res = *(volatile u64 *)p; break;		\
 	default:							\
-		_abort(); /* hack for userspace */			\
+		abort(); /* hack for userspace */			\
 	}								\
 })
 
@@ -130,7 +133,7 @@ static inline unsigned long __cmpxchg##sfx(volatile void *ptr,		\
 	case 8:								\
 		return __cmpxchg_case##sfx##_8(ptr, old, new);		\
 	default:							\
-		_abort(); /* hack for userspace */			\
+		abort(); /* hack for userspace */			\
 	}								\
 }
 
@@ -249,7 +252,7 @@ static inline void __cmpwait##sfx(volatile void *ptr,			\
 	case 8:								\
 		return __cmpwait_case##sfx##_8(ptr, val);		\
 	default:							\
-		_abort(); /* hack for userspace */			\
+		abort(); /* hack for userspace */			\
 	}								\
 }
 
diff --git a/main.c b/main.c
index 589ce79..5f143c5 100644
--- a/main.c
+++ b/main.c
@@ -1,6 +1,8 @@
 #include "qrwlock.h"
 
+unsigned long __rmem_stop_addr = 0x0;
 struct qrwlock lock = __ARCH_RW_LOCK_UNLOCKED;
+static int count = 0;
 
 /*
  * Test driver for qrwlock.
@@ -8,14 +10,22 @@ struct qrwlock lock = __ARCH_RW_LOCK_UNLOCKED;
  */
 static void writer(void)
 {
+#if 0
 	arch_write_lock(&lock);
+	count = 1;
+	barrier();
+	count = 2;
 	arch_write_unlock(&lock);
+#endif
+	exit();
 }
 
 static void reader(void)
 {
 	arch_read_lock(&lock);
+	assert(count != 1);
 	arch_read_unlock(&lock);
+	exit();
 }
 
 void _start(void)
diff --git a/rmem.h b/rmem.h
index 77f0986..ab66735 100644
--- a/rmem.h
+++ b/rmem.h
@@ -3,8 +3,12 @@
 
 #include "compiler.h"
 
-static inline void __noreturn __rmem_stop(void)
+extern unsigned long __rmem_stop_addr;
+
+static inline void __noreturn __rmem_stop(unsigned long pc)
 {
+	__rmem_stop_addr = pc;
+
 	while (1)
 		asm volatile(".inst	0xd50bb001");
 }