From 82ef8ada82bd63ea7ce61843189fd4ee5de45cb5 Mon Sep 17 00:00:00 2001 From: Benjamin Barenblat Date: Fri, 17 Jun 2016 09:49:24 -0700 Subject: [PATCH] src/commonlib/lz4_wrapper: Correct inline asm for unaligned 64-bit copy Rewrite inline assembly for ARMv7+ to correctly annotate inputs and outputs. On ARM GCC 6.1.1, this causes assembly output to change from the incorrect @ r0 is allocated to hold dst and x0 @ r1 is allocated to hold src and x1 ldr r0, [r1] @ clobbers dst! ldr r1, [r1, #4] str r0, [r0] str r1, [r0, #4] to the correct @ r0 is allocated to hold dst @ r1 is allocated to hold src and x1 @ r3 is allocated to hold x0 ldr r3, [r1] ldr r1, [r1, #4] str r3, [r0] str r1, [r0, #4] Also modify checkpatch.pl to ignore spaces before opening brackets when used in inline assembly. Change-Id: I255995f5e0a7b1a95375258755a93972c51d79b8 Signed-off-by: Benjamin Barenblat Reviewed-on: https://review.coreboot.org/15216 Tested-by: build bot (Jenkins) Reviewed-by: Julius Werner Reviewed-by: Paul Menzel --- src/commonlib/lz4_wrapper.c | 22 +++++++++++++--------- util/lint/checkpatch.pl | 4 +++- 2 files changed, 16 insertions(+), 10 deletions(-) diff --git a/src/commonlib/lz4_wrapper.c b/src/commonlib/lz4_wrapper.c index 93fa7e8e1d..0342868d74 100644 --- a/src/commonlib/lz4_wrapper.c +++ b/src/commonlib/lz4_wrapper.c @@ -1,5 +1,5 @@ /* - * Copyright 2015 Google Inc. + * Copyright 2015-2016 Google Inc. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions @@ -54,14 +54,18 @@ static void LZ4_copy8(void *dst, const void *src) ((uint8_t *)dst)[i] = ((uint8_t *)src)[i]; #else uint32_t x0, x1; - __asm__ volatile ( - "ldr %[x0], [%[src]]\n\t" - "ldr %[x1], [%[src], #4]\n\t" - "str %[x0], [%[dst]]\n\t" - "str %[x1], [%[dst], #4]\n\t" - : [x0]"=r"(x0), [x1]"=r"(x1) - : [src]"r"(src), [dst]"r"(dst) - : "memory" ); + __asm__ ("ldr %[x0], [%[src]]" + : [x0]"=r"(x0) + : [src]"r"(src), "m"(*(const uint32_t *)src)); + __asm__ ("ldr %[x1], [%[src], #4]" + : [x1]"=r"(x1) + : [src]"r"(src), "m"(*(const uint32_t *)(src + 4))); + __asm__ ("str %[x0], [%[dst]]" + : "=m"(*(uint32_t *)dst) + : [x0]"r"(x0), [dst]"r"(dst)); + __asm__ ("str %[x1], [%[dst], #4]" + : "=m"(*(uint32_t *)(dst + 4)) + : [x1]"r"(x1), [dst]"r"(dst)); #endif #elif defined(__riscv__) /* RISC-V implementations may trap on any unaligned access. */ diff --git a/util/lint/checkpatch.pl b/util/lint/checkpatch.pl index 3a4b8be455..45445043e7 100755 --- a/util/lint/checkpatch.pl +++ b/util/lint/checkpatch.pl @@ -3,6 +3,7 @@ # (c) 2005, Joel Schopp (the ugly bit) # (c) 2007,2008, Andy Whitcroft (new conditions, test suite) # (c) 2008-2010 Andy Whitcroft +# (c) 2016 Google Inc. # Licensed under the terms of the GNU GPL License version 2 use strict; @@ -3377,11 +3378,12 @@ sub process { # 1. with a type on the left -- int [] a; # 2. at the beginning of a line for slice initialisers -- [0...10] = 5, # 3. inside a curly brace -- = { [0...10] = 5 } +# 4. in an extended asm instruction -- : [r0]"r"(r0) while ($line =~ /(.*?\s)\[/g) { my ($where, $prefix) = ($-[1], $1); if ($prefix !~ /$Type\s+$/ && ($where != 0 || $prefix !~ /^.\s+$/) && - $prefix !~ /[{,]\s+$/) { + $prefix !~ /[{,:]\s+$/) { if (ERROR("BRACKET_SPACE", "space prohibited before open square bracket '['\n" . $herecurr) && $fix) {