From 3b2fcb3ef6f00d026f06ca154060b29ded3eb3fc Mon Sep 17 00:00:00 2001
From: Chris Robinson <chris.kcat@gmail.com>
Date: Mon, 2 Jun 2014 19:19:22 -0700
Subject: Avoid a loop when updating the source position variables

---
 Alc/ALu.c              | 12 ++++++++----
 Alc/mixer.c            | 10 ++++------
 OpenAL32/Include/alu.h |  2 ++
 3 files changed, 14 insertions(+), 10 deletions(-)

diff --git a/Alc/ALu.c b/Alc/ALu.c
index 82932cf3..e661af1d 100644
--- a/Alc/ALu.c
+++ b/Alc/ALu.c
@@ -34,12 +34,16 @@
 #include "alu.h"
 #include "bs2b.h"
 #include "hrtf.h"
+#include "static_assert.h"
 
 #include "mixer_defs.h"
 
 #include "midi/base.h"
 
 
+static_assert((INT_MAX>>FRACTIONBITS)/MAX_PITCH > BUFFERSIZE,
+              "MAX_PITCH and/or BUFFERSIZE are too large for FRACTIONBITS!");
+
 struct ChanMap {
     enum Channel channel;
     ALfloat angle;
@@ -330,8 +334,8 @@ ALvoid CalcNonAttnSourceParams(ALactivesource *src, const ALCcontext *ALContext)
         if((ALBuffer=BufferListItem->buffer) != NULL)
         {
             Pitch = Pitch * ALBuffer->Frequency / Frequency;
-            if(Pitch > 10.0f)
-                src->Step = 10<<FRACTIONBITS;
+            if(Pitch > (ALfloat)MAX_PITCH)
+                src->Step = MAX_PITCH<<FRACTIONBITS;
             else
             {
                 src->Step = fastf2i(Pitch*FRACTIONONE);
@@ -955,8 +959,8 @@ ALvoid CalcSourceParams(ALactivesource *src, const ALCcontext *ALContext)
             /* Calculate fixed-point stepping value, based on the pitch, buffer
              * frequency, and output frequency. */
             Pitch = Pitch * ALBuffer->Frequency / Frequency;
-            if(Pitch > 10.0f)
-                src->Step = 10<<FRACTIONBITS;
+            if(Pitch > (ALfloat)MAX_PITCH)
+                src->Step = MAX_PITCH<<FRACTIONBITS;
             else
             {
                 src->Step = fastf2i(Pitch*FRACTIONONE);
diff --git a/Alc/mixer.c b/Alc/mixer.c
index ef1517b3..8830a3fe 100644
--- a/Alc/mixer.c
+++ b/Alc/mixer.c
@@ -383,12 +383,10 @@ ALvoid MixSource(ALactivesource *src, ALCdevice *Device, ALuint SamplesToDo)
             }
         }
         /* Update positions */
-        for(j = 0;j < DstBufferSize;j++)
-        {
-            DataPosFrac += increment;
-            DataPosInt  += DataPosFrac>>FRACTIONBITS;
-            DataPosFrac &= FRACTIONMASK;
-        }
+        DataPosFrac += increment*DstBufferSize;
+        DataPosInt  += DataPosFrac>>FRACTIONBITS;
+        DataPosFrac &= FRACTIONMASK;
+
         OutPos += DstBufferSize;
         src->Offset += DstBufferSize;
         src->Direct.Counter = maxu(src->Direct.Counter, DstBufferSize) - DstBufferSize;
diff --git a/OpenAL32/Include/alu.h b/OpenAL32/Include/alu.h
index 98663c7d..c4b4d674 100644
--- a/OpenAL32/Include/alu.h
+++ b/OpenAL32/Include/alu.h
@@ -34,6 +34,8 @@
 #define SRC_HISTORY_LENGTH (1<<SRC_HISTORY_BITS)
 #define SRC_HISTORY_MASK   (SRC_HISTORY_LENGTH-1)
 
+#define MAX_PITCH  (10)
+
 
 #ifdef __cplusplus
 extern "C" {
-- 
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