[Xen-devel] [PATCH 6/7] x86/asm: Fold LOAD_C_CLOBBERED into RESTORE_ALL

[Andrew Cooper <andrew.cooper3@xxxxxxxxxx>]

With its sole other user removed, fold LOAD_C_CLOBBERED into RESTORE_ALL to
reduce the cognitive load of trying to work out which registers get modified.

No functional change.

Signed-off-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
---
CC: Jan Beulich <JBeulich@xxxxxxxx>
---
 xen/include/asm-x86/asm_defns.h | 27 ++++++---------------------
 1 file changed, 6 insertions(+), 21 deletions(-)

diff --git a/xen/include/asm-x86/asm_defns.h b/xen/include/asm-x86/asm_defns.h
index f1c6fa1..11306d1 100644
--- a/xen/include/asm-x86/asm_defns.h
+++ b/xen/include/asm-x86/asm_defns.h
@@ -321,40 +321,25 @@ static always_inline void stac(void)
 .endif
 
 /*
- * Reload registers not preserved by C code from frame.
- *
- * @compat: R8-R11 don't need reloading
+ * Restore all previously saved registers.
  *
- * For the way it is used in RESTORE_ALL, this macro must preserve EFLAGS.ZF.
+ * @adj: extra stack pointer adjustment to be folded into the adjustment done
+ *       anyway at the end of the macro
+ * @compat: R8-R15 don't need reloading
  */
-.macro LOAD_C_CLOBBERED compat=0 ax=1
+.macro RESTORE_ALL adj=0 compat=0
 .if !\compat
+        testl $TRAP_regs_dirty,UREGS_entry_vector(%rsp)
         movq  UREGS_r11(%rsp),%r11
         movq  UREGS_r10(%rsp),%r10
         movq  UREGS_r9(%rsp),%r9
         movq  UREGS_r8(%rsp),%r8
 .endif
-.if \ax
         LOAD_ONE_REG(ax, \compat)
-.endif
         LOAD_ONE_REG(cx, \compat)
         LOAD_ONE_REG(dx, \compat)
         LOAD_ONE_REG(si, \compat)
         LOAD_ONE_REG(di, \compat)
-.endm
-
-/*
- * Restore all previously saved registers.
- *
- * @adj: extra stack pointer adjustment to be folded into the adjustment done
- *       anyway at the end of the macro
- * @compat: R8-R15 don't need reloading
- */
-.macro RESTORE_ALL adj=0 compat=0
-.if !\compat
-        testl $TRAP_regs_dirty,UREGS_entry_vector(%rsp)
-.endif
-        LOAD_C_CLOBBERED \compat
 .if !\compat
         jz    987f
         movq  UREGS_r15(%rsp),%r15
-- 
2.1.4


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