[Qemu-devel] [PULL 21/29] tcg-i386: Adjust tcg_out_tlb_load for x32

[Richard Henderson <rth@twiddle.net>]

Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Richard Henderson <rth@twiddle.net>
---
 tcg/i386/tcg-target.c | 41 +++++++++++++++++++++++++++--------------
 1 file changed, 27 insertions(+), 14 deletions(-)

diff --git a/tcg/i386/tcg-target.c b/tcg/i386/tcg-target.c
index 247c9d2..cde134f 100644
--- a/tcg/i386/tcg-target.c
+++ b/tcg/i386/tcg-target.c
@@ -1085,33 +1085,46 @@ static inline void tcg_out_tlb_load(TCGContext *s, int addrlo_idx,
     const int addrlo = args[addrlo_idx];
     const int r0 = TCG_REG_L0;
     const int r1 = TCG_REG_L1;
-    TCGType type = TCG_TYPE_I32;
-    int rexw = 0;
+    TCGType ttype = TCG_TYPE_I32;
+    TCGType htype = TCG_TYPE_I32;
+    int trexw = 0, hrexw = 0;
 
-    if (TCG_TARGET_REG_BITS == 64 && TARGET_LONG_BITS == 64) {
-        type = TCG_TYPE_I64;
-        rexw = P_REXW;
+    if (TCG_TARGET_REG_BITS == 64) {
+        if (TARGET_LONG_BITS == 64) {
+            ttype = TCG_TYPE_I64;
+            trexw = P_REXW;
+        }
+        if (TCG_TYPE_PTR == TCG_TYPE_I64) {
+            htype = TCG_TYPE_I64;
+            hrexw = P_REXW;
+        }
     }
 
-    tcg_out_mov(s, type, r0, addrlo);
-    tcg_out_mov(s, type, r1, addrlo);
+    tcg_out_mov(s, htype, r0, addrlo);
+    tcg_out_mov(s, ttype, r1, addrlo);
 
-    tcg_out_shifti(s, SHIFT_SHR + rexw, r0,
+    tcg_out_shifti(s, SHIFT_SHR + hrexw, r0,
                    TARGET_PAGE_BITS - CPU_TLB_ENTRY_BITS);
 
-    tgen_arithi(s, ARITH_AND + rexw, r1,
+    tgen_arithi(s, ARITH_AND + trexw, r1,
                 TARGET_PAGE_MASK | ((1 << s_bits) - 1), 0);
-    tgen_arithi(s, ARITH_AND + rexw, r0,
+    tgen_arithi(s, ARITH_AND + hrexw, r0,
                 (CPU_TLB_SIZE - 1) << CPU_TLB_ENTRY_BITS, 0);
 
-    tcg_out_modrm_sib_offset(s, OPC_LEA + P_REXW, r0, TCG_AREG0, r0, 0,
+    tcg_out_modrm_sib_offset(s, OPC_LEA + hrexw, r0, TCG_AREG0, r0, 0,
                              offsetof(CPUArchState, tlb_table[mem_index][0])
                              + which);
 
     /* cmp 0(r0), r1 */
-    tcg_out_modrm_offset(s, OPC_CMP_GvEv + rexw, r1, r0, 0);
+    tcg_out_modrm_offset(s, OPC_CMP_GvEv + trexw, r1, r0, 0);
 
-    tcg_out_mov(s, type, r1, addrlo);
+    /* Prepare for both the fast path add of the tlb addend, and the slow
+       path function argument setup.  There are two cases worth note:
+       For 32-bit guest and x86_64 host, MOVL zero-extends the guest address
+       before the fastpath ADDQ below.  For 64-bit guest and x32 host, MOVQ
+       copies the entire guest address for the slow path, while truncation
+       for the 32-bit host happens with the fastpath ADDL below.  */
+    tcg_out_mov(s, ttype, r1, addrlo);
 
     /* jne slow_path */
     tcg_out_opc(s, OPC_JCC_long + JCC_JNE, 0, 0, 0);
@@ -1131,7 +1144,7 @@ static inline void tcg_out_tlb_load(TCGContext *s, int addrlo_idx,
     /* TLB Hit.  */
 
     /* add addend(r0), r1 */
-    tcg_out_modrm_offset(s, OPC_ADD_GvEv + P_REXW, r1, r0,
+    tcg_out_modrm_offset(s, OPC_ADD_GvEv + hrexw, r1, r0,
                          offsetof(CPUTLBEntry, addend) - which);
 }
 #elif defined(__x86_64__) && defined(__linux__)
-- 
1.8.1.4