Merge branch '285-discrete_cdf-is-incorrectly-used-by-some-prngs' int…

…o 'develop_stream' Use discrete_alias instead of discrete_cdf with all PRNGs Closes #285 See merge request amd/libraries/rocRAND!333
ROCm · Jul 9, 2024 · 615fc5a · 615fc5a
2 parents 8f7e2af + 23dc7c9
commit 615fc5a
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diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -3,6 +3,12 @@
 Documentation for rocRAND is available at
 [https://rocm.docs.amd.com/projects/rocRAND/en/latest/](https://rocm.docs.amd.com/projects/rocRAND/en/latest/)
 
+## (Unreleased) rocRAND-3.2.0 for ROCm 6.3.0
+
+### Changes
+
+* `rocrand_discrete` for MTGP32, LFSR113 and ThreeFry generators now uses the alias method, which is faster than binary search in CDF.
+
 ## (Unreleased) rocRAND-3.1.1 for ROCm 6.2.0
 
 ## Fixes

diff --git a/library/include/rocrand/rocrand_discrete.h b/library/include/rocrand/rocrand_discrete.h
@@ -281,7 +281,7 @@ __forceinline__ __device__ unsigned int
     rocrand_discrete(rocrand_state_mtgp32*               state,
                      const rocrand_discrete_distribution discrete_distribution)
 {
-    return rocrand_device::detail::discrete_cdf(rocrand(state), *discrete_distribution);
+    return rocrand_device::detail::discrete_alias(rocrand(state), *discrete_distribution);
 }
 
 /**
@@ -376,7 +376,7 @@ __forceinline__ __device__ __host__ unsigned int
     rocrand_discrete(rocrand_state_lfsr113*              state,
                      const rocrand_discrete_distribution discrete_distribution)
 {
-    return rocrand_device::detail::discrete_cdf(rocrand(state), *discrete_distribution);
+    return rocrand_device::detail::discrete_alias(rocrand(state), *discrete_distribution);
 }
 
 /**
@@ -395,7 +395,7 @@ __forceinline__ __device__ __host__ unsigned int
     rocrand_discrete(rocrand_state_threefry2x32_20*      state,
                      const rocrand_discrete_distribution discrete_distribution)
 {
-    return rocrand_device::detail::discrete_cdf(rocrand(state), *discrete_distribution);
+    return rocrand_device::detail::discrete_alias(rocrand(state), *discrete_distribution);
 }
 
 /**
@@ -414,7 +414,7 @@ __forceinline__ __device__ __host__ unsigned int
     rocrand_discrete(rocrand_state_threefry2x64_20*      state,
                      const rocrand_discrete_distribution discrete_distribution)
 {
-    return rocrand_device::detail::discrete_cdf(rocrand(state), *discrete_distribution);
+    return rocrand_device::detail::discrete_alias(rocrand(state), *discrete_distribution);
 }
 
 /**
@@ -433,7 +433,7 @@ __forceinline__ __device__ __host__ unsigned int
     rocrand_discrete(rocrand_state_threefry4x32_20*      state,
                      const rocrand_discrete_distribution discrete_distribution)
 {
-    return rocrand_device::detail::discrete_cdf(rocrand(state), *discrete_distribution);
+    return rocrand_device::detail::discrete_alias(rocrand(state), *discrete_distribution);
 }
 
 /**
@@ -452,7 +452,7 @@ __forceinline__ __device__ __host__ unsigned int
     rocrand_discrete(rocrand_state_threefry4x64_20*      state,
                      const rocrand_discrete_distribution discrete_distribution)
 {
-    return rocrand_device::detail::discrete_cdf(rocrand(state), *discrete_distribution);
+    return rocrand_device::detail::discrete_alias(rocrand(state), *discrete_distribution);
 }
 
 /** @} */ // end of group rocranddevice