Help a bit the compiler to provide better code:
unsigned int f(int i)
{
return 1 << (31 - i);
}
unsigned int g(int i)
{
return 0x80000000 >> i;
}
Disassembly of section .text:
00000000 <f>:
0: 20 63 00 1f subfic r3,r3,31
4: 39 20 00 01 li r9,1
8: 7d 23 18 30 slw r3,r9,r3
c: 4e 80 00 20 blr
00000010 <g>:
10: 3d 20 80 00 lis r9,-32768
14: 7d 23 1c 30 srw r3,r9,r3
18: 4e 80 00 20 blr
Signed-off-by: Christophe Leroy <christophe.le...@c-s.fr>
---
arch/powerpc/sysdev/cpm1.c | 24 ++++++++++--------------
1 file changed, 10 insertions(+), 14 deletions(-)
diff --git a/arch/powerpc/sysdev/cpm1.c b/arch/powerpc/sysdev/cpm1.c
index dc3653da6dd1..2b0bb55612d2 100644
--- a/arch/powerpc/sysdev/cpm1.c
+++ b/arch/powerpc/sysdev/cpm1.c
@@ -307,7 +307,7 @@ struct cpm_ioport32e {
static void cpm1_set_pin32(int port, int pin, int flags)
{
struct cpm_ioport32e __iomem *iop;
- pin = 1 << (31 - pin);
+ pin = 0x80000000 >> pin;
if (port == CPM_PORTB)
iop = (struct cpm_ioport32e __iomem *)
@@ -351,7 +351,7 @@ static void cpm1_set_pin16(int port, int pin, int flags)
struct cpm_ioport16 __iomem *iop =
(struct cpm_ioport16 __iomem *)&mpc8xx_immr->im_ioport;
- pin = 1 << (15 - pin);
+ pin = 0x8000 >> pin;
if (port != 0)
iop += port - 1;
@@ -550,9 +550,7 @@ static int cpm1_gpio16_get(struct gpio_chip *gc, unsigned
int gpio)
{
struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc);
struct cpm_ioport16 __iomem *iop = mm_gc->regs;
- u16 pin_mask;
-
- pin_mask = 1 << (15 - gpio);
+ u16 pin_mask = pin_mask = 0x8000 >> gpio;
return !!(in_be16(&iop->dat) & pin_mask);
}
@@ -576,7 +574,7 @@ static void cpm1_gpio16_set(struct gpio_chip *gc, unsigned
int gpio, int value)
struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc);
struct cpm1_gpio16_chip *cpm1_gc = gpiochip_get_data(&mm_gc->gc);
unsigned long flags;
- u16 pin_mask = 1 << (15 - gpio);
+ u16 pin_mask = 0x8000 >> gpio;
spin_lock_irqsave(&cpm1_gc->lock, flags);
@@ -599,7 +597,7 @@ static int cpm1_gpio16_dir_out(struct gpio_chip *gc,
unsigned int gpio, int val)
struct cpm1_gpio16_chip *cpm1_gc = gpiochip_get_data(&mm_gc->gc);
struct cpm_ioport16 __iomem *iop = mm_gc->regs;
unsigned long flags;
- u16 pin_mask = 1 << (15 - gpio);
+ u16 pin_mask = 0x8000 >> gpio;
spin_lock_irqsave(&cpm1_gc->lock, flags);
@@ -617,7 +615,7 @@ static int cpm1_gpio16_dir_in(struct gpio_chip *gc,
unsigned int gpio)
struct cpm1_gpio16_chip *cpm1_gc = gpiochip_get_data(&mm_gc->gc);
struct cpm_ioport16 __iomem *iop = mm_gc->regs;
unsigned long flags;
- u16 pin_mask = 1 << (15 - gpio);
+ u16 pin_mask = 0x8000 >> gpio;
spin_lock_irqsave(&cpm1_gc->lock, flags);
@@ -684,9 +682,7 @@ static int cpm1_gpio32_get(struct gpio_chip *gc, unsigned
int gpio)
{
struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc);
struct cpm_ioport32b __iomem *iop = mm_gc->regs;
- u32 pin_mask;
-
- pin_mask = 1 << (31 - gpio);
+ u32 pin_mask = 0x80000000 >> gpio;
return !!(in_be32(&iop->dat) & pin_mask);
}
@@ -710,7 +706,7 @@ static void cpm1_gpio32_set(struct gpio_chip *gc, unsigned
int gpio, int value)
struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc);
struct cpm1_gpio32_chip *cpm1_gc = gpiochip_get_data(&mm_gc->gc);
unsigned long flags;
- u32 pin_mask = 1 << (31 - gpio);
+ u32 pin_mask = 0x80000000 >> gpio;
spin_lock_irqsave(&cpm1_gc->lock, flags);
@@ -725,7 +721,7 @@ static int cpm1_gpio32_dir_out(struct gpio_chip *gc,
unsigned int gpio, int val)
struct cpm1_gpio32_chip *cpm1_gc = gpiochip_get_data(&mm_gc->gc);
struct cpm_ioport32b __iomem *iop = mm_gc->regs;
unsigned long flags;
- u32 pin_mask = 1 << (31 - gpio);
+ u32 pin_mask = 0x80000000 >> gpio;
spin_lock_irqsave(&cpm1_gc->lock, flags);
@@ -743,7 +739,7 @@ static int cpm1_gpio32_dir_in(struct gpio_chip *gc,
unsigned int gpio)
struct cpm1_gpio32_chip *cpm1_gc = gpiochip_get_data(&mm_gc->gc);
struct cpm_ioport32b __iomem *iop = mm_gc->regs;
unsigned long flags;
- u32 pin_mask = 1 << (31 - gpio);
+ u32 pin_mask = 0x80000000 >> gpio;
spin_lock_irqsave(&cpm1_gc->lock, flags);
--
2.12.0
