[coreboot-gerrit] New patch to review for coreboot: vendorcode/amd: Fix non-terminating loop

[Patrick Georgi]

Patrick Georgi ([e-mail]) just uploaded a new patch set to gerrit, which you can find at https://review.coreboot.org/17834

-gerrit

commit 0bf3aeff3b5e5a7f9778a5550d24e7f1932ba87d
Author: Patrick Georgi 
Date:   Tue Dec 13 15:42:58 2016 +0100

vendorcode/amd: Fix non-terminating loop

Code is copied from agesa/common's amdlib.c.
    Things can probably be deduplicated.

Change-Id: I9c8adab5db7e9fd41aecc522136dfa705c1e2ee6
    Signed-off-by: Patrick Georgi 
    Found-by: Coverity Scan #1229662
---
 src/vendorcode/amd/pi/Lib/amdlib.c | 16 +++++++++++-----
 1 file changed, 11 insertions(+), 5 deletions(-)

diff --git a/src/vendorcode/amd/pi/Lib/amdlib.c b/src/vendorcode/amd/pi/Lib/amdlib.c
index 4c8a56d..03ca207 100644
--- a/src/vendorcode/amd/pi/Lib/amdlib.c
+++ b/src/vendorcode/amd/pi/Lib/amdlib.c
@@ -381,11 +381,17 @@ LibAmdBitScanReverse (
   IN       UINT32 value
 )
 {
-  UINTN Index;
-  for (Index = 31; Index >= 0; Index--){
-      if (value & (1 << Index)) break;
-  }
-  return (UINT8) Index;
+  uint8_t bit = 31;
+  do {
+    if (value & (1 << 31))
+      return bit;
+
+    value <<= 1;
+    bit--;
+
+  } while (value != 0);
+
+  return 0xFF; /* Error code indicating no bit found */
 }

AMDLIB_OPTIMIZE