From 2c8fd1142a9bf025d14be732be00f34ad33af131 Mon Sep 17 00:00:00 2001
From: Yann Collet <cyan@fb.com>
Date: Tue, 13 Sep 2022 17:34:08 -0700
Subject: removed a few more usages of base ptr

by making LZ4_putPosition() specific to byPtr strategy.
byU32 and byU16 use LZ4_putIndexOnHash() instead.

In both cases, it makes it irrelevant to pass` base as reference ptr.
---
 lib/lz4.c | 35 ++++++++++++++++++++---------------
 1 file changed, 20 insertions(+), 15 deletions(-)

diff --git a/lib/lz4.c b/lib/lz4.c
index ee6d209..955e864 100644
--- a/lib/lz4.c
+++ b/lib/lz4.c
@@ -804,22 +804,16 @@ LZ4_FORCE_INLINE void LZ4_putIndexOnHash(U32 idx, U32 h, void* tableBase, tableT
 }
 
 LZ4_FORCE_INLINE void LZ4_putPositionOnHash(const BYTE* p, U32 h,
-                                  void* tableBase, tableType_t const tableType,
-                            const BYTE* srcBase)
+                                  void* tableBase, tableType_t const tableType)
 {
-    switch (tableType)
-    {
-    case clearedTable: { /* illegal! */ assert(0); return; }
-    case byPtr: { const BYTE** hashTable = (const BYTE**)tableBase; hashTable[h] = p; return; }
-    case byU32: { U32* hashTable = (U32*) tableBase; hashTable[h] = (U32)(p-srcBase); return; }
-    case byU16: { U16* hashTable = (U16*) tableBase; hashTable[h] = (U16)(p-srcBase); return; }
-    }
+    assert(tableType == byPtr); (void)tableType;
+    { const BYTE** hashTable = (const BYTE**)tableBase; hashTable[h] = p; return; }
 }
 
-LZ4_FORCE_INLINE void LZ4_putPosition(const BYTE* p, void* tableBase, tableType_t tableType, const BYTE* srcBase)
+LZ4_FORCE_INLINE void LZ4_putPosition(const BYTE* p, void* tableBase, tableType_t tableType)
 {
     U32 const h = LZ4_hashPosition(p, tableType);
-    LZ4_putPositionOnHash(p, h, tableBase, tableType, srcBase);
+    LZ4_putPositionOnHash(p, h, tableBase, tableType);
 }
 
 /* LZ4_getIndexOnHash() :
@@ -979,7 +973,12 @@ LZ4_FORCE_INLINE int LZ4_compress_generic_validated(
     if (inputSize<LZ4_minLength) goto _last_literals;        /* Input too small, no compression (all literals) */
 
     /* First Byte */
-    LZ4_putPosition(ip, cctx->hashTable, tableType, base);
+    {   U32 const h = LZ4_hashPosition(ip, tableType);
+        if (tableType == byPtr) {
+            LZ4_putPositionOnHash(ip, h, cctx->hashTable, tableType);
+        } else {
+            LZ4_putIndexOnHash(startIndex, h, cctx->hashTable, tableType);
+    }   }
     ip++; forwardH = LZ4_hashPosition(ip, tableType);
 
     /* Main Loop */
@@ -1004,7 +1003,7 @@ LZ4_FORCE_INLINE int LZ4_compress_generic_validated(
 
                 match = LZ4_getPositionOnHash(h, cctx->hashTable, tableType);
                 forwardH = LZ4_hashPosition(forwardIp, tableType);
-                LZ4_putPositionOnHash(ip, h, cctx->hashTable, tableType, base);
+                LZ4_putPositionOnHash(ip, h, cctx->hashTable, tableType);
 
             } while ( (match+LZ4_DISTANCE_MAX < ip)
                    || (LZ4_read32(match) != LZ4_read32(ip)) );
@@ -1202,13 +1201,19 @@ _next_match:
         if (ip >= mflimitPlusOne) break;
 
         /* Fill table */
-        LZ4_putPosition(ip-2, cctx->hashTable, tableType, base);
+        {   U32 const h = LZ4_hashPosition(ip-2, tableType);
+            if (tableType == byPtr) {
+                LZ4_putPositionOnHash(ip-2, h, cctx->hashTable, tableType);
+            } else {
+                U32 const idx = (U32)((ip-2) - base);
+                LZ4_putIndexOnHash(idx, h, cctx->hashTable, tableType);
+        }   }
 
         /* Test next position */
         if (tableType == byPtr) {
 
             match = LZ4_getPosition(ip, cctx->hashTable, tableType);
-            LZ4_putPosition(ip, cctx->hashTable, tableType, base);
+            LZ4_putPosition(ip, cctx->hashTable, tableType);
             if ( (match+LZ4_DISTANCE_MAX >= ip)
               && (LZ4_read32(match) == LZ4_read32(ip)) )
             { token=op++; *token=0; goto _next_match; }
-- 
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