]> www.infradead.org Git - users/dwmw2/qemu.git/commitdiff
tcg/i386: Generalize multi-part load overlap test
authorRichard Henderson <richard.henderson@linaro.org>
Sun, 16 Apr 2023 13:56:41 +0000 (15:56 +0200)
committerRichard Henderson <richard.henderson@linaro.org>
Fri, 5 May 2023 16:10:59 +0000 (17:10 +0100)
Test for both base and index; use datahi as a temporary, overwritten
by the final load.  Always perform the loads in ascending order, so
that any (user-only) fault sees the correct address.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
tcg/i386/tcg-target.c.inc

index cfa2349b03a30c3aeda22d95ce29c527900729f5..173f3c3172d03c380957de0a19a9c7f96f1359e5 100644 (file)
@@ -2221,23 +2221,22 @@ static void tcg_out_qemu_ld_direct(TCGContext *s, TCGReg datalo, TCGReg datahi,
         if (TCG_TARGET_REG_BITS == 64) {
             tcg_out_modrm_sib_offset(s, movop + P_REXW + seg, datalo,
                                      base, index, 0, ofs);
+            break;
+        }
+        if (use_movbe) {
+            TCGReg t = datalo;
+            datalo = datahi;
+            datahi = t;
+        }
+        if (base == datalo || index == datalo) {
+            tcg_out_modrm_sib_offset(s, OPC_LEA, datahi, base, index, 0, ofs);
+            tcg_out_modrm_offset(s, movop + seg, datalo, datahi, 0);
+            tcg_out_modrm_offset(s, movop + seg, datahi, datahi, 4);
         } else {
-            if (use_movbe) {
-                TCGReg t = datalo;
-                datalo = datahi;
-                datahi = t;
-            }
-            if (base != datalo) {
-                tcg_out_modrm_sib_offset(s, movop + seg, datalo,
-                                         base, index, 0, ofs);
-                tcg_out_modrm_sib_offset(s, movop + seg, datahi,
-                                         base, index, 0, ofs + 4);
-            } else {
-                tcg_out_modrm_sib_offset(s, movop + seg, datahi,
-                                         base, index, 0, ofs + 4);
-                tcg_out_modrm_sib_offset(s, movop + seg, datalo,
-                                         base, index, 0, ofs);
-            }
+            tcg_out_modrm_sib_offset(s, movop + seg, datalo,
+                                     base, index, 0, ofs);
+            tcg_out_modrm_sib_offset(s, movop + seg, datahi,
+                                     base, index, 0, ofs + 4);
         }
         break;
     default: