[PATCH v2] Make iwmmxt.S support Clang's integrated assembler
From: Jian Cai
Date: Fri Nov 06 2020 - 19:11:26 EST
This patch replaces 6 IWMMXT instructions Clang's integrated assembler
does not support in iwmmxt.S using macros, while making sure GNU
assembler still emit the same instructions. This should be easier than
providing full IWMMXT support in Clang.
"Intel Wireless MMX Technology - Developer Guide - August, 2002" should
be referenced for the encoding schemes of these extensions.
Link: https://github.com/ClangBuiltLinux/linux/issues/975
Suggested-by: Nick Desaulniers <ndesaulniers@xxxxxxxxxx>
Suggested-by: Ard Biesheuvel <ardb@xxxxxxxxxx>
Signed-off-by: Jian Cai <jiancai@xxxxxxxxxx>
---
arch/arm/kernel/iwmmxt.S | 89 ++++++++++++++++++++--------------------
arch/arm/kernel/iwmmxt.h | 47 +++++++++++++++++++++
2 files changed, 92 insertions(+), 44 deletions(-)
create mode 100644 arch/arm/kernel/iwmmxt.h
diff --git a/arch/arm/kernel/iwmmxt.S b/arch/arm/kernel/iwmmxt.S
index 0dcae787b004..d2b4ac06e4ed 100644
--- a/arch/arm/kernel/iwmmxt.S
+++ b/arch/arm/kernel/iwmmxt.S
@@ -16,6 +16,7 @@
#include <asm/thread_info.h>
#include <asm/asm-offsets.h>
#include <asm/assembler.h>
+#include "iwmmxt.h"
#if defined(CONFIG_CPU_PJ4) || defined(CONFIG_CPU_PJ4B)
#define PJ4(code...) code
@@ -113,33 +114,33 @@ concan_save:
concan_dump:
- wstrw wCSSF, [r1, #MMX_WCSSF]
- wstrw wCASF, [r1, #MMX_WCASF]
- wstrw wCGR0, [r1, #MMX_WCGR0]
- wstrw wCGR1, [r1, #MMX_WCGR1]
- wstrw wCGR2, [r1, #MMX_WCGR2]
- wstrw wCGR3, [r1, #MMX_WCGR3]
+ wstrw wCSSF, r1, MMX_WCSSF
+ wstrw wCASF, r1, MMX_WCASF
+ wstrw wCGR0, r1, MMX_WCGR0
+ wstrw wCGR1, r1, MMX_WCGR1
+ wstrw wCGR2, r1, MMX_WCGR2
+ wstrw wCGR3, r1, MMX_WCGR3
1: @ MUP? wRn
tst r2, #0x2
beq 2f
- wstrd wR0, [r1, #MMX_WR0]
- wstrd wR1, [r1, #MMX_WR1]
- wstrd wR2, [r1, #MMX_WR2]
- wstrd wR3, [r1, #MMX_WR3]
- wstrd wR4, [r1, #MMX_WR4]
- wstrd wR5, [r1, #MMX_WR5]
- wstrd wR6, [r1, #MMX_WR6]
- wstrd wR7, [r1, #MMX_WR7]
- wstrd wR8, [r1, #MMX_WR8]
- wstrd wR9, [r1, #MMX_WR9]
- wstrd wR10, [r1, #MMX_WR10]
- wstrd wR11, [r1, #MMX_WR11]
- wstrd wR12, [r1, #MMX_WR12]
- wstrd wR13, [r1, #MMX_WR13]
- wstrd wR14, [r1, #MMX_WR14]
- wstrd wR15, [r1, #MMX_WR15]
+ wstrd wR0, r1, MMX_WR0
+ wstrd wR1, r1, MMX_WR1
+ wstrd wR2, r1, MMX_WR2
+ wstrd wR3, r1, MMX_WR3
+ wstrd wR4, r1, MMX_WR4
+ wstrd wR5, r1, MMX_WR5
+ wstrd wR6, r1, MMX_WR6
+ wstrd wR7, r1, MMX_WR7
+ wstrd wR8, r1, MMX_WR8
+ wstrd wR9, r1, MMX_WR9
+ wstrd wR10, r1, MMX_WR10
+ wstrd wR11, r1, MMX_WR11
+ wstrd wR12, r1, MMX_WR12
+ wstrd wR13, r1, MMX_WR13
+ wstrd wR14, r1, MMX_WR14
+ wstrd wR15, r1, MMX_WR15
2: teq r0, #0 @ anything to load?
reteq lr @ if not, return
@@ -147,30 +148,30 @@ concan_dump:
concan_load:
@ Load wRn
- wldrd wR0, [r0, #MMX_WR0]
- wldrd wR1, [r0, #MMX_WR1]
- wldrd wR2, [r0, #MMX_WR2]
- wldrd wR3, [r0, #MMX_WR3]
- wldrd wR4, [r0, #MMX_WR4]
- wldrd wR5, [r0, #MMX_WR5]
- wldrd wR6, [r0, #MMX_WR6]
- wldrd wR7, [r0, #MMX_WR7]
- wldrd wR8, [r0, #MMX_WR8]
- wldrd wR9, [r0, #MMX_WR9]
- wldrd wR10, [r0, #MMX_WR10]
- wldrd wR11, [r0, #MMX_WR11]
- wldrd wR12, [r0, #MMX_WR12]
- wldrd wR13, [r0, #MMX_WR13]
- wldrd wR14, [r0, #MMX_WR14]
- wldrd wR15, [r0, #MMX_WR15]
+ wldrd wR0, r0, MMX_WR0
+ wldrd wR1, r0, MMX_WR1
+ wldrd wR2, r0, MMX_WR2
+ wldrd wR3, r0, MMX_WR3
+ wldrd wR4, r0, MMX_WR4
+ wldrd wR5, r0, MMX_WR5
+ wldrd wR6, r0, MMX_WR6
+ wldrd wR7, r0, MMX_WR7
+ wldrd wR8, r0, MMX_WR8
+ wldrd wR9, r0, MMX_WR9
+ wldrd wR10, r0, MMX_WR10
+ wldrd wR11, r0, MMX_WR11
+ wldrd wR12, r0, MMX_WR12
+ wldrd wR13, r0, MMX_WR13
+ wldrd wR14, r0, MMX_WR14
+ wldrd wR15, r0, MMX_WR15
@ Load wCx
- wldrw wCSSF, [r0, #MMX_WCSSF]
- wldrw wCASF, [r0, #MMX_WCASF]
- wldrw wCGR0, [r0, #MMX_WCGR0]
- wldrw wCGR1, [r0, #MMX_WCGR1]
- wldrw wCGR2, [r0, #MMX_WCGR2]
- wldrw wCGR3, [r0, #MMX_WCGR3]
+ wldrw wCSSF, r0, MMX_WCSSF
+ wldrw wCASF, r0, MMX_WCASF
+ wldrw wCGR0, r0, MMX_WCGR0
+ wldrw wCGR1, r0, MMX_WCGR1
+ wldrw wCGR2, r0, MMX_WCGR2
+ wldrw wCGR3, r0, MMX_WCGR3
@ clear CUP/MUP (only if r1 != 0)
teq r1, #0
diff --git a/arch/arm/kernel/iwmmxt.h b/arch/arm/kernel/iwmmxt.h
new file mode 100644
index 000000000000..fb627286f5bb
--- /dev/null
+++ b/arch/arm/kernel/iwmmxt.h
@@ -0,0 +1,47 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef __IWMMXT_H__
+#define __IWMMXT_H__
+
+.irp b, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15
+.set .LwR\b, \b
+.set .Lr\b, \b
+.endr
+
+.set .LwCSSF, 0x2
+.set .LwCASF, 0x3
+.set .LwCGR0, 0x8
+.set .LwCGR1, 0x9
+.set .LwCGR2, 0xa
+.set .LwCGR3, 0xb
+
+.macro wldrd, reg:req, base:req, offset:req
+.inst 0xedd00100 | (.L\reg << 12) | (.L\base << 16) | (\offset >> 2)
+.endm
+
+.macro wldrw, reg:req, base:req, offset:req
+.inst 0xfd900100 | (.L\reg << 12) | (.L\base << 16) | (\offset >> 2)
+.endm
+
+.macro wstrd, reg:req, base:req, offset:req
+.inst 0xedc00100 | (.L\reg << 12) | (.L\base << 16) | (\offset >> 2)
+.endm
+
+.macro wstrw, reg:req, base:req, offset:req
+.inst 0xfd800100 | (.L\reg << 12) | (.L\base << 16) | (\offset >> 2)
+.endm
+
+#ifdef __clang__
+
+#define wCon c1
+
+.macro tmrc, dest:req, control:req
+mrc p1, 0, \dest, \control, c0, 0
+.endm
+
+.macro tmcr, control:req, src:req
+mcr p1, 0, \src, \control, c0, 0
+.endm
+#endif
+
+#endif
--
2.29.1.341.ge80a0c044ae-goog