From 2074a3b29169308bbb42f88cc1fcb9be0af20ee7 Mon Sep 17 00:00:00 2001
From: David Green <david.green@arm.com>
Date: Sun, 7 Mar 2021 14:38:03 +0000
Subject: [PATCH] CMSIS-DSP: Ensure correlation array index is signed.

This attempts to ensures that even on a 64bit system, the array access
will be treated as a negative number, not a large unsigned offset ending
up reading from the middle of nowhere.
---
 Source/FilteringFunctions/arm_correlate_f16.c | 2 +-
 Source/FilteringFunctions/arm_correlate_f32.c | 2 +-
 Source/FilteringFunctions/arm_correlate_q15.c | 2 +-
 Source/FilteringFunctions/arm_correlate_q31.c | 2 +-
 Source/FilteringFunctions/arm_correlate_q7.c  | 2 +-
 5 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/Source/FilteringFunctions/arm_correlate_f16.c b/Source/FilteringFunctions/arm_correlate_f16.c
index 960577de..6e9c2183 100755
--- a/Source/FilteringFunctions/arm_correlate_f16.c
+++ b/Source/FilteringFunctions/arm_correlate_f16.c
@@ -1136,7 +1136,7 @@ void arm_correlate_f16(
       if ((((i - j) < srcBLen) && (j < srcALen)))
       {
         /* z[i] += x[i-j] * y[j] */
-        sum += pIn1[j] * pIn2[-((int32_t) i - j)];
+        sum += pIn1[j] * pIn2[-((int32_t) i - (int32_t) j)];
       }
     }
 
diff --git a/Source/FilteringFunctions/arm_correlate_f32.c b/Source/FilteringFunctions/arm_correlate_f32.c
index 839049b3..a0805f1e 100644
--- a/Source/FilteringFunctions/arm_correlate_f32.c
+++ b/Source/FilteringFunctions/arm_correlate_f32.c
@@ -1074,7 +1074,7 @@ void arm_correlate_f32(
       if ((((i - j) < srcBLen) && (j < srcALen)))
       {
         /* z[i] += x[i-j] * y[j] */
-        sum += pIn1[j] * pIn2[-((int32_t) i - j)];
+        sum += pIn1[j] * pIn2[-((int32_t) i - (int32_t) j)];
       }
     }
 
diff --git a/Source/FilteringFunctions/arm_correlate_q15.c b/Source/FilteringFunctions/arm_correlate_q15.c
index 270eda70..ac1a6307 100644
--- a/Source/FilteringFunctions/arm_correlate_q15.c
+++ b/Source/FilteringFunctions/arm_correlate_q15.c
@@ -882,7 +882,7 @@ void arm_correlate_q15(
       if (((i - j) < srcBLen) && (j < srcALen))
       {
         /* z[i] += x[i-j] * y[j] */
-        sum += ((q31_t) pIn1[j] * pIn2[-((int32_t) i - j)]);
+        sum += ((q31_t) pIn1[j] * pIn2[-((int32_t) i - (int32_t) j)]);
       }
     }
 
diff --git a/Source/FilteringFunctions/arm_correlate_q31.c b/Source/FilteringFunctions/arm_correlate_q31.c
index c6bb38ec..59fbd166 100644
--- a/Source/FilteringFunctions/arm_correlate_q31.c
+++ b/Source/FilteringFunctions/arm_correlate_q31.c
@@ -858,7 +858,7 @@ void arm_correlate_q31(
       if (((i - j) < srcBLen) && (j < srcALen))
       {
         /* z[i] += x[i-j] * y[j] */
-        sum += ((q63_t) pIn1[j] * pIn2[-((int32_t) i - j)]);
+        sum += ((q63_t) pIn1[j] * pIn2[-((int32_t) i - (int32_t) j)]);
       }
     }
 
diff --git a/Source/FilteringFunctions/arm_correlate_q7.c b/Source/FilteringFunctions/arm_correlate_q7.c
index 965c5a94..bcd6cdae 100644
--- a/Source/FilteringFunctions/arm_correlate_q7.c
+++ b/Source/FilteringFunctions/arm_correlate_q7.c
@@ -981,7 +981,7 @@ void arm_correlate_q7(
       if (((i - j) < srcBLen) && (j < srcALen))
       {
         /* z[i] += x[i-j] * y[j] */
-        sum += ((q15_t) pIn1[j] * pIn2[-((int32_t) i - j)]);
+        sum += ((q15_t) pIn1[j] * pIn2[-((int32_t) i - (int32_t) j)]);
       }
     }