From 3c76ace36bc7dccafaae24c2c4452fb5e767c0fd Mon Sep 17 00:00:00 2001 From: Mateusz Guzik Date: Sat, 8 Dec 2018 04:53:08 +0000 Subject: [PATCH] amd64: stop re-reading curpc on subyte/suword Originally read value is still safely kept. Re-reading code was there for previous iterations which were partially shared with i386. Sponsored by: The FreeBSD Foundation --- sys/amd64/amd64/support.S | 4 ---- 1 file changed, 4 deletions(-) diff --git a/sys/amd64/amd64/support.S b/sys/amd64/amd64/support.S index 2f2897613d16..05e5f988f2b6 100644 --- a/sys/amd64/amd64/support.S +++ b/sys/amd64/amd64/support.S @@ -1155,7 +1155,6 @@ ENTRY(suword16_nosmap) movw %si,(%rdi) xorl %eax,%eax - movq PCPU(CURPCB),%rcx /* restore trashed register */ movq %rax,PCB_ONFAULT(%rcx) POP_FRAME_POINTER ret @@ -1174,7 +1173,6 @@ ENTRY(suword16_smap) movw %si,(%rdi) clac xorl %eax,%eax - movq PCPU(CURPCB),%rcx /* restore trashed register */ movq %rax,PCB_ONFAULT(%rcx) POP_FRAME_POINTER ret @@ -1192,7 +1190,6 @@ ENTRY(subyte_nosmap) movl %esi,%eax movb %al,(%rdi) xorl %eax,%eax - movq PCPU(CURPCB),%rcx /* restore trashed register */ movq %rax,PCB_ONFAULT(%rcx) POP_FRAME_POINTER ret @@ -1212,7 +1209,6 @@ ENTRY(subyte_smap) movb %al,(%rdi) clac xorl %eax,%eax - movq PCPU(CURPCB),%rcx /* restore trashed register */ movq %rax,PCB_ONFAULT(%rcx) POP_FRAME_POINTER ret