[Qemu-devel] [PATCH] target-or32: fix masking in openrisc_pic_cpu_handler()

[Xi Wang]

A correct mask should be `x & (1 << i)', rather than `x && (1 << i)'.

Also, in C99 signed shift (1 << 31) is undefined behavior, since the
result exceeds INT_MAX; use 1U instead.

Signed-off-by: Xi Wang <address@hidden>
---
 hw/openrisc_pic.c |    8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/hw/openrisc_pic.c b/hw/openrisc_pic.c
index aaeb9a9..4f6d5a0 100644
--- a/hw/openrisc_pic.c
+++ b/hw/openrisc_pic.c
@@ -26,12 +26,14 @@ static void openrisc_pic_cpu_handler(void *opaque, int irq, 
int level)
 {
     OpenRISCCPU *cpu = (OpenRISCCPU *)opaque;
     int i;
-    uint32_t irq_bit = 1 << irq;
+    uint32_t irq_bit;
 
     if (irq > 31 || irq < 0) {
         return;
     }
 
+    irq_bit = 1U << irq;
+
     if (level) {
         cpu->env.picsr |= irq_bit;
     } else {
@@ -39,11 +41,11 @@ static void openrisc_pic_cpu_handler(void *opaque, int irq, 
int level)
     }
 
     for (i = 0; i < 32; i++) {
-        if ((cpu->env.picsr && (1 << i)) && (cpu->env.picmr && (1 << i))) {
+        if ((cpu->env.picsr & (1U << i)) && (cpu->env.picmr & (1U << i))) {
             cpu_interrupt(&cpu->env, CPU_INTERRUPT_HARD);
         } else {
             cpu_reset_interrupt(&cpu->env, CPU_INTERRUPT_HARD);
-            cpu->env.picsr &= ~(1 << i);
+            cpu->env.picsr &= ~(1U << i);
         }
     }
 }
-- 
1.7.10.4