From b288f6278ee449a0d08a4c6b642b7d01c7c72f08 Mon Sep 17 00:00:00 2001
From: gbeauche <>
Date: Sat, 1 Apr 2006 21:41:19 +0000
Subject: [PATCH] Helper macros to annotate likely branch directions. Colateral
 effect: this also fixes build with GCC 4.1 (ppc-dyngen-ops.cpp) since the
 branches are re-ordered in a way there is now only one exit-point in
 op_jump_next_A0().

---
 SheepShaver/src/Unix/sysdeps.h                    | 15 +++++++++++++++
 .../src/kpx_cpu/src/cpu/ppc/ppc-dyngen-ops.cpp    |  4 ++--
 2 files changed, 17 insertions(+), 2 deletions(-)

diff --git a/SheepShaver/src/Unix/sysdeps.h b/SheepShaver/src/Unix/sysdeps.h
index 1a96daba..7f8aeb0a 100644
--- a/SheepShaver/src/Unix/sysdeps.h
+++ b/SheepShaver/src/Unix/sysdeps.h
@@ -166,6 +166,21 @@ typedef int64 intptr;
 #error "Unsupported size of pointer"
 #endif
 
+/**
+ *		Helper macros to annotate likely branch directions
+ **/
+
+#if __GNUC__ >= 3 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 96)
+#define likely(x)		__builtin_expect((x),1)
+#define unlikely(x)		__builtin_expect((x),0)
+#endif
+#ifndef likely
+#define likely(x)		(x)
+#endif
+#ifndef unlikely
+#define unlikely(x)		(x)
+#endif
+
 /**
  *		Helper functions to byteswap data
  **/
diff --git a/SheepShaver/src/kpx_cpu/src/cpu/ppc/ppc-dyngen-ops.cpp b/SheepShaver/src/kpx_cpu/src/cpu/ppc/ppc-dyngen-ops.cpp
index 0ec0f89f..75557572 100644
--- a/SheepShaver/src/kpx_cpu/src/cpu/ppc/ppc-dyngen-ops.cpp
+++ b/SheepShaver/src/kpx_cpu/src/cpu/ppc/ppc-dyngen-ops.cpp
@@ -1246,10 +1246,10 @@ void OPPROTO op_dcbz_T0(void)
 void OPPROTO op_jump_next_A0(void)
 {
 	// Make sure there is no pending interrupt request
-	if (powerpc_dyngen_helper::spcflags().empty()) {
+	if (likely(powerpc_dyngen_helper::spcflags().empty())) {
 		powerpc_block_info *bi = (powerpc_block_info *)reg_A0;
 		uint32 pc = powerpc_dyngen_helper::get_pc();
-		if (bi->pc == pc || (bi = powerpc_dyngen_helper::find_block(pc)) != NULL)
+		if (likely(bi->pc == pc) || likely((bi = powerpc_dyngen_helper::find_block(pc)) != NULL))
 			goto *(bi->entry_point);
 	}
 	dyngen_barrier();