Avoid undefined shift exponent in f2Pow().
Bug: 146938418
Test: atest DecoderTestXheAac ; atest DecoderTestAacDrc
Change-Id: Id28608e049244968158900848c23bf7a8298083d
diff --git a/libFDK/include/fixpoint_math.h b/libFDK/include/fixpoint_math.h
index 373eec1..51df4d7 100644
--- a/libFDK/include/fixpoint_math.h
+++ b/libFDK/include/fixpoint_math.h
@@ -775,7 +775,7 @@
/**
* \brief return (base_m * 2^base_e) ^ N
- * \param base_m mantissa of the base
+ * \param base_m mantissa of the base. Must not be negative.
* \param base_e exponent of the base
* \param N power to be calculated of the base
* \param result_e pointer to a INT where the exponent of the result will be
diff --git a/libFDK/src/fixpoint_math.cpp b/libFDK/src/fixpoint_math.cpp
index 6c656fa..1e26420 100644
--- a/libFDK/src/fixpoint_math.cpp
+++ b/libFDK/src/fixpoint_math.cpp
@@ -1,7 +1,7 @@
/* -----------------------------------------------------------------------------
Software License for The Fraunhofer FDK AAC Codec Library for Android
-© Copyright 1995 - 2018 Fraunhofer-Gesellschaft zur Förderung der angewandten
+© Copyright 1995 - 2020 Fraunhofer-Gesellschaft zur Förderung der angewandten
Forschung e.V. All rights reserved.
1. INTRODUCTION
@@ -650,6 +650,12 @@
INT ans_lg2_e, baselg2_e;
FIXP_DBL base_lg2, ans_lg2, result;
+ if (base_m <= (FIXP_DBL)0) {
+ result = (FIXP_DBL)0;
+ *result_e = 0;
+ return result;
+ }
+
/* Calc log2 of base */
base_lg2 = fLog2(base_m, base_e, &baselg2_e);
