From 73b683a288ce52d6cba2254f408d6c3688cd26e9 Mon Sep 17 00:00:00 2001
From: MITSUNARI Shigeo <herumi@nifty.com>
Date: Fri, 23 Nov 2018 17:50:54 +0900
Subject: [PATCH] setByCSPRNG uses setArrayMask to be compatible to setHashOf

---
 include/mcl/fp.hpp    | 16 +++-------------
 src/fp.cpp            | 15 ---------------
 test/fp_util_test.cpp | 35 -----------------------------------
 3 files changed, 3 insertions(+), 63 deletions(-)

diff --git a/include/mcl/fp.hpp b/include/mcl/fp.hpp
index eb70d50..a8e9ac8 100644
--- a/include/mcl/fp.hpp
+++ b/include/mcl/fp.hpp
@@ -70,16 +70,6 @@ inline void dumpUnit(Unit x)
 
 bool isEnableJIT(); // 1st call is not threadsafe
 
-void getRandVal(bool *pb, void *p, RandGen& rg, const Unit *in, size_t bitSize);
-#ifndef CYBOZU_DONT_USE_EXCEPTION
-inline void getRandVal(void *p, RandGen& rg, const Unit *in, size_t bitSize)
-{
-	bool b;
-	getRandVal(&b, p, rg, in, bitSize);
-	if (!b) throw cybozu::Exception("getRandVal") << bitSize;
-}
-#endif
-
 uint32_t sha256(void *out, uint32_t maxOutSize, const void *msg, uint32_t msgSize);
 uint32_t sha512(void *out, uint32_t maxOutSize, const void *msg, uint32_t msgSize);
 
@@ -350,9 +340,9 @@ public:
 	void setByCSPRNG(bool *pb, fp::RandGen rg = fp::RandGen())
 	{
 		if (rg.isZero()) rg = fp::RandGen::get();
-		fp::getRandVal(pb, v_, rg, op_.p, op_.bitSize);
-		if (!*pb) return;
-		toMont();
+		rg.read(pb, v_, op_.N * sizeof(Unit)); // byte size
+		if (!pb) return;
+		setArrayMask(v_, op_.N);
 	}
 #ifndef CYBOZU_DONT_USE_EXCEPTION
 	void setByCSPRNG(fp::RandGen rg = fp::RandGen())
diff --git a/src/fp.cpp b/src/fp.cpp
index 7296353..75f2932 100644
--- a/src/fp.cpp
+++ b/src/fp.cpp
@@ -120,21 +120,6 @@ bool isEnableJIT()
 #endif
 }
 
-void getRandVal(bool *pb, void *p, RandGen& rg, const Unit *in, size_t bitSize)
-{
-	if (rg.isZero()) rg = RandGen::get();
-	Unit *out = reinterpret_cast<Unit*>(p);
-	const size_t n = (bitSize + UnitBitSize - 1) / UnitBitSize;
-	const size_t rem = bitSize & (UnitBitSize - 1);
-	assert(n > 0);
-	for (;;) {
-		rg.read(pb, out, n * sizeof(Unit)); // byte size
-		if (!*pb) return;
-		if (rem > 0) out[n - 1] &= (Unit(1) << rem) - 1;
-		if (isLessArray(out, in, n)) return;
-	}
-}
-
 uint32_t sha256(void *out, uint32_t maxOutSize, const void *msg, uint32_t msgSize)
 {
 	const uint32_t hashSize = 256 / 8;
diff --git a/test/fp_util_test.cpp b/test/fp_util_test.cpp
index b6d5efc..e8a9f9a 100644
--- a/test/fp_util_test.cpp
+++ b/test/fp_util_test.cpp
@@ -195,41 +195,6 @@ struct Rand {
 	}
 };
 
-CYBOZU_TEST_AUTO(getRandVal)
-{
-	const size_t rn = 8;
-	const struct {
-		uint32_t r[rn];
-		uint32_t mod[2];
-		size_t bitSize;
-		uint32_t expect[2];
-	} tbl[] = {
-		{ { 1, 2, 3, 4, 5, 6, 7, 8 }, { 5, 6 }, 64, { 1, 2 } },
-		{ { 0xfffffffc, 0x7, 3, 4, 5, 6, 7, 8 }, { 0xfffffffe, 0x3 }, 34, { 0xfffffffc, 0x3 } },
-		{ { 0xfffffffc, 0x7, 3, 4, 5, 6, 7, 8 }, { 0xfffffffb, 0x3 }, 34, { 3, 0 } },
-		{ { 2, 3, 5, 7, 4, 3, 0, 3 }, { 1, 0x3 }, 34, { 0, 3 } },
-	};
-	for (size_t i = 0; i < CYBOZU_NUM_OF_ARRAY(tbl); i++) {
-		Rand rg(tbl[i].r, rn);
-#if CYBOZU_OS_BIT == 64
-		uint64_t out[1];
-#else
-		uint32_t out[2];
-#endif
-		mcl::fp::RandGen wrg(rg);
-#if CYBOZU_OS_BIT == 64
-		uint64_t mod = tbl[i].mod[0] | (uint64_t(tbl[i].mod[1]) << 32);
-		mcl::fp::getRandVal(out, wrg, &mod, tbl[i].bitSize);
-		uint64_t expect = tbl[i].expect[0] | (uint64_t(tbl[i].expect[1]) << 32);
-		CYBOZU_TEST_EQUAL(out[0], expect);
-#else
-		mcl::fp::getRandVal(out, wrg, tbl[i].mod, tbl[i].bitSize);
-		CYBOZU_TEST_EQUAL(out[0], tbl[i].expect[0]);
-		CYBOZU_TEST_EQUAL(out[1], tbl[i].expect[1]);
-#endif
-	}
-}
-
 CYBOZU_TEST_AUTO(maskArray)
 {
 #if 1