Changeset 1959528 for libcfa/src/stdlib.cfa

Timestamp:

Jan 12, 2022, 6:34:58 PM (2 years ago)

Author:

Peter A. Buhr <pabuhr@…>

Branches:

ADT, ast-experimental, enum, forall-pointer-decay, master, pthread-emulation, qualifiedEnum

Children:

00f5fde

Parents:

a10f6b4

Message:

third attempt at specialized PRNG

File:

• libcfa/src/stdlib.cfa (modified) (2 diffs)

libcfa/src/stdlib.cfa

@@ -10 +10 @@
 // Created On       : Thu Jan 28 17:10:29 2016
 // Last Modified By : Peter A. Buhr
-// Last Modified On : Mon Jan 10 17:07:21 2022
-// Update Count     : 572
+// Last Modified On : Wed Jan 12 16:25:36 2022
+// Update Count     : 578
 //
 
@@ -223 +223 @@
 //---------------------------------------
 
+// Pipelined to allow OoO overlap with reduced dependencies. Critically, return the current value, and compute and store
+// the next value.
+
 #define GENERATOR LCG
 
-inline uint32_t MarsagliaXor( uint32_t & state ) {
+static inline uint32_t MarsagliaXor( uint32_t & state ) {
+        uint32_t ret = state;
         state ^= state << 6;
         state ^= state >> 21;
         state ^= state << 7;
-        return state;
+        return ret;
 } // MarsagliaXor
 
-inline uint32_t LCG( uint32_t & state ) {                               // linear congruential generator
-        return state = 36969 * (state & 65535) + (state >> 16); // 36969 is NOT prime!
+static inline uint32_t LCG( uint32_t & state ) {                // linear congruential generator
+        uint32_t ret = state;
+        state = 36969 * (state & 65535) + (state >> 16);        // 36969 is NOT prime! No not change it!
+        return ret;
 } // LCG
 
-uint32_t __thread_seed = rdtscl();                                              // global thread seed
-
-void set_seed( uint32_t seed ) { __thread_seed = seed; }
-uint32_t get_seed() { return  __thread_seed; }
+uint32_t __global_random_seed;
+
+void set_seed( PRNG & prng, uint32_t seed_ ) with( prng ) { state = seed = seed_; GENERATOR( state ); } // set seed
 uint32_t prng( PRNG & prng ) with( prng ) { callcnt += 1; return GENERATOR( state ); }
 
-uint32_t prng( void ) { return GENERATOR( __thread_seed ); } // [0,UINT_MAX]
+void set_seed( uint32_t seed ) {
+        active_thread()->random_state = __global_random_seed = seed;
+        GENERATOR( active_thread()->random_state );
+} // set_seed
+uint32_t get_seed() { return __global_random_seed; }
+uint32_t prng( void ) { return GENERATOR( active_thread()->random_state ); } // [0,UINT_MAX]
 
 //---------------------------------------