[x86] Revert some changes which seem to cause regressions when compiling fsharp.

diff --git a/mono/mini/mini-x86.c b/mono/mini/mini-x86.c
index 598e0144823f750c4429e3baced00512834934b8..cf4919b8aefe191aecc8ad5c4258ed99bf720c36 100755 (executable)
--- a/mono/mini/mini-x86.c
+++ b/mono/mini/mini-x86.c
@@ -5339,15 +5339,29 @@ mono_arch_emit_prolog (MonoCompile *cfg)
        pos = 0;
 
        if (!method->save_lmf) {
-               for (i = 0; i < X86_NREG; ++i) {
-                       if ((cfg->used_int_regs & X86_CALLER_REGS & (1 << i)) && (i != X86_EBP)) {
-                               x86_push_reg (code, i);
-                               pos += 4;
-                               cfa_offset += sizeof (gpointer);
-                               mono_emit_unwind_op_offset (cfg, code, i, - cfa_offset);
-                               /* These are handled automatically by the stack marking code */
-                               mini_gc_set_slot_type_from_cfa (cfg, - cfa_offset, SLOT_NOREF);
-                       }
+               if (cfg->used_int_regs & (1 << X86_EBX)) {
+                       x86_push_reg (code, X86_EBX);
+                       pos += 4;
+                       cfa_offset += sizeof (gpointer);
+                       mono_emit_unwind_op_offset (cfg, code, X86_EBX, - cfa_offset);
+                       /* These are handled automatically by the stack marking code */
+                       mini_gc_set_slot_type_from_cfa (cfg, - cfa_offset, SLOT_NOREF);
+               }
+
+               if (cfg->used_int_regs & (1 << X86_EDI)) {
+                       x86_push_reg (code, X86_EDI);
+                       pos += 4;
+                       cfa_offset += sizeof (gpointer);
+                       mono_emit_unwind_op_offset (cfg, code, X86_EDI, - cfa_offset);
+                       mini_gc_set_slot_type_from_cfa (cfg, - cfa_offset, SLOT_NOREF);
+               }
+
+               if (cfg->used_int_regs & (1 << X86_ESI)) {
+                       x86_push_reg (code, X86_ESI);
+                       pos += 4;
+                       cfa_offset += sizeof (gpointer);
+                       mono_emit_unwind_op_offset (cfg, code, X86_ESI, - cfa_offset);
+                       mini_gc_set_slot_type_from_cfa (cfg, - cfa_offset, SLOT_NOREF);
                }
        }
 
@@ -5595,9 +5609,19 @@ mono_arch_emit_epilog (MonoCompile *cfg)
                        x86_lea_membase (code, X86_ESP, X86_EBP, pos);
                }
 
-               for (i = X86_NREG - 1; i >= 0; --i) {
-                       if ((cfg->used_int_regs & X86_CALLER_REGS & (1 << i)) && (i != X86_EBP))
-                               x86_pop_reg (code, i);
+               if (pos) {
+                       g_assert (need_stack_frame);
+                       x86_lea_membase (code, X86_ESP, X86_EBP, pos);
+               }
+
+               if (cfg->used_int_regs & (1 << X86_ESI)) {
+                       x86_pop_reg (code, X86_ESI);
+               }
+               if (cfg->used_int_regs & (1 << X86_EDI)) {
+                       x86_pop_reg (code, X86_EDI);
+               }
+               if (cfg->used_int_regs & (1 << X86_EBX)) {
+                       x86_pop_reg (code, X86_EBX);
                }
        }