commit 767c250310ee0494d37bf7514d24973dd50e38ea
author Richard Henderson <richard.henderson@linaro.org> Wed Apr 05 21:39:54 2023 -0700
committer Richard Henderson <richard.henderson@linaro.org> Sun Apr 23 08:46:45 2023 +0100
tree d9058dbb599095acdca3d67288041bf7873e2a16
parent b3dfd5fc181433bd43e2163b1a94b11a548edfba

tcg: Introduce tcg_out_xchg

We will want a backend interface for register swapping.
This is only properly defined for x86; all others get a
stub version that always indicates failure.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

tcg/i386/tcg-target.c.inc

diff --git a/tcg/i386/tcg-target.c.inc b/tcg/i386/tcg-target.c.inc
index f8c0eed..c8e2bf5 100644
--- a/tcg/i386/tcg-target.c.inc
+++ b/tcg/i386/tcg-target.c.inc
@@ -460,6 +460,7 @@
 #define OPC_VPTERNLOGQ  (0x25 | P_EXT3A | P_DATA16 | P_VEXW | P_EVEX)
 #define OPC_VZEROUPPER  (0x77 | P_EXT)
 #define OPC_XCHG_ax_r32	(0x90)
+#define OPC_XCHG_EvGv   (0x87)
 
 #define OPC_GRP3_Eb     (0xf6)
 #define OPC_GRP3_Ev     (0xf7)
@@ -1078,6 +1079,13 @@
     }
 }
 
+static bool tcg_out_xchg(TCGContext *s, TCGType type, TCGReg r1, TCGReg r2)
+{
+    int rexw = type == TCG_TYPE_I32 ? 0 : P_REXW;
+    tcg_out_modrm(s, OPC_XCHG_EvGv + rexw, r1, r2);
+    return true;
+}
+
 static void tcg_out_addi_ptr(TCGContext *s, TCGReg rd, TCGReg rs,
                              tcg_target_long imm)
 {