From: drh <drh@noemail.net>
Date: Tue, 6 Dec 2011 13:24:59 +0000 (+0000)
Subject: Do not reuse temp registers originally allocated to a subroutine within
X-Git-Tag: mountain-lion~9^2~5
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=cdc695571629850086a5d990c0026c5e69b32536;p=thirdparty%2Fsqlite.git

Do not reuse temp registers originally allocated to a subroutine within
the main body of the program logic, since if the subroutine is called
while the reused temp registers are in use, their values will get clobbered.
Candidate fix for ticket [3a77c9714e63330]

FossilOrigin-Name: 092d53315e50be42b51ef7b3069c82c32a129b6a
---

diff --git a/manifest b/manifest
index ef618fe69b..5fc0d1a877 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Merge\sthe\swinGetLastError\sfixes\sinto\strunk.
-D 2011-12-06T00:47:51.936
+C Do\snot\sreuse\stemp\sregisters\soriginally\sallocated\sto\sa\ssubroutine\swithin\nthe\smain\sbody\sof\sthe\sprogram\slogic,\ssince\sif\sthe\ssubroutine\sis\scalled\nwhile\sthe\sreused\stemp\sregisters\sare\sin\suse,\stheir\svalues\swill\sget\sclobbered.\nCandidate\sfix\sfor\sticket\s[3a77c9714e63330]
+D 2011-12-06T13:24:59.067
 F Makefile.arm-wince-mingw32ce-gcc d6df77f1f48d690bd73162294bbba7f59507c72f
 F Makefile.in 5b4a3e12a850b021547e43daf886b25133b44c07
 F Makefile.linux-gcc 91d710bdc4998cb015f39edf3cb314ec4f4d7e23
@@ -134,7 +134,7 @@ F src/complete.c dc1d136c0feee03c2f7550bafc0d29075e36deac
 F src/ctime.c a9c26822515f81ec21588cbb482ca6724be02e33
 F src/date.c 067a81c9942c497aafd2c260e13add8a7d0c7dd4
 F src/delete.c 51d32f0a9c880663e54ce309f52e40c325d5e112
-F src/expr.c fbf116f90cabc917ae50bba24a73a0b55519a0c8
+F src/expr.c 319db0ad9f3c5d039d54bf5a65c98c08c7233924
 F src/fault.c 160a0c015b6c2629d3899ed2daf63d75754a32bb
 F src/fkey.c 657212460bf5cfd3ae607d12ea62092844c227b5
 F src/func.c 6261ce00aad9c63cd5b4219249b05683979060e9
@@ -180,11 +180,11 @@ F src/printf.c 03104cbff6959ff45df69dc9060ba6212f60a869
 F src/random.c cd4a67b3953b88019f8cd4ccd81394a8ddfaba50
 F src/resolve.c 365ab1c870e38596d6869e76fb544fe6e4ffc809
 F src/rowset.c 69afa95a97c524ba6faf3805e717b5b7ae85a697
-F src/select.c 80f3ac44a8514b1d107b80f5df4a424ae059d2b6
+F src/select.c 538b5f096f6aacedf717bf982f9ad9a901008514
 F src/shell.c 29812a900a780eb0f835c4bc65e216272689def8
 F src/sqlite.h.in 57081d8e6b53ce29541d7437c93bce6087ac53b5
 F src/sqlite3ext.h 6904f4aadf976f95241311fbffb00823075d9477
-F src/sqliteInt.h 6f28b69d77356b1e45c024a6c103a1e0f0ec9f62
+F src/sqliteInt.h 142ef5ed3fe0e6c662e99dbf92f38715b29a53b6
 F src/sqliteLimit.h 164b0e6749d31e0daa1a4589a169d31c0dec7b3d
 F src/status.c 4568e72dfd36b6a5911f93457364deb072e0b03a
 F src/table.c 2cd62736f845d82200acfa1287e33feb3c15d62e
@@ -976,7 +976,7 @@ F tool/tostr.awk e75472c2f98dd76e06b8c9c1367f4ab07e122d06
 F tool/vdbe-compress.tcl d70ea6d8a19e3571d7ab8c9b75cba86d1173ff0f
 F tool/warnings-clang.sh 9f406d66e750e8ac031c63a9ef3248aaa347ef2a
 F tool/warnings.sh fbc018d67fd7395f440c28f33ef0f94420226381
-P 431556cac0b2c86d7f6a60412ff1023feeaafedf 7e657bbb800107c992a6ee7a3b35bc0a073bf3e4
-R 543654dfa3532b18db5b62d6f330a3c2
+P 5b03ba9db0d23a8597b45e00ad5892c8065ce1cd
+R 9fd2e18e31f5993e2a2417d0bd31fbb8
 U drh
-Z d9a349b5feef66c92d693305f283c870
+Z 6b588a9e7cf08c9f198f7cca1fb8c358
diff --git a/manifest.uuid b/manifest.uuid
index fb1da87359..0f043b6cf3 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-5b03ba9db0d23a8597b45e00ad5892c8065ce1cd
\ No newline at end of file
+092d53315e50be42b51ef7b3069c82c32a129b6a
\ No newline at end of file
diff --git a/src/expr.c b/src/expr.c
index d506173771..e8a9d64108 100644
--- a/src/expr.c
+++ b/src/expr.c
@@ -3762,3 +3762,11 @@ void sqlite3ReleaseTempRange(Parse *pParse, int iReg, int nReg){
     pParse->iRangeReg = iReg;
   }
 }
+
+/*
+** Mark all temporary registers as being unavailable for reuse.
+*/
+void sqlite3ClearTempRegCache(Parse *pParse){
+  pParse->nTempReg = 0;
+  pParse->nRangeReg = 0;
+}
diff --git a/src/select.c b/src/select.c
index 571a77822b..da75a51cd9 100644
--- a/src/select.c
+++ b/src/select.c
@@ -3860,7 +3860,7 @@ int sqlite3Select(
       retAddr = sqlite3VdbeAddOp1(v, OP_Return, pItem->regReturn);
       VdbeComment((v, "end %s", pItem->pTab->zName));
       sqlite3VdbeChangeP1(v, topAddr, retAddr);
-
+      sqlite3ClearTempRegCache(pParse);
     }
     if( /*pParse->nErr ||*/ db->mallocFailed ){
       goto select_end;
diff --git a/src/sqliteInt.h b/src/sqliteInt.h
index 4e00ad03c1..890f44f5e1 100644
--- a/src/sqliteInt.h
+++ b/src/sqliteInt.h
@@ -2660,6 +2660,7 @@ int sqlite3GetTempReg(Parse*);
 void sqlite3ReleaseTempReg(Parse*,int);
 int sqlite3GetTempRange(Parse*,int);
 void sqlite3ReleaseTempRange(Parse*,int,int);
+void sqlite3ClearTempRegCache(Parse*);
 Expr *sqlite3ExprAlloc(sqlite3*,int,const Token*,int);
 Expr *sqlite3Expr(sqlite3*,int,const char*);
 void sqlite3ExprAttachSubtrees(sqlite3*,Expr*,Expr*,Expr*);