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Willy Tarreau b107f7bdd9 Fix switch/case on uint64_t
The switch/case operation was entirely performed on int64_t, resulting
in a warning and bad code to be emitted on 64 bit machines when used on
an unsigned long with a case range whose signed representation starts
positive and ends negative like in the example below:

  #include <limits.h>
  #include <stdio.h>
  #include <stdlib.h>

  int nbdg(unsigned long n)
  {
  	switch (n) {
  	case                    1UL ...                   9UL: return 1;
  	case                   10UL ...                  99UL: return 2;
  	case                  100UL ...                 999UL: return 3;
  	case                 1000UL ...                9999UL: return 4;
  	case                10000UL ...               99999UL: return 5;
  	case               100000UL ...              999999UL: return 6;
  	case              1000000UL ...             9999999UL: return 7;
  	case             10000000UL ...            99999999UL: return 8;
  	case            100000000UL ...           999999999UL: return 9;
  	case           1000000000UL ...          9999999999UL: return 10;
  	case          10000000000UL ...         99999999999UL: return 11;
  	case         100000000000UL ...        999999999999UL: return 12;
  	case        1000000000000UL ...       9999999999999UL: return 13;
  	case       10000000000000UL ...      99999999999999UL: return 14;
  	case      100000000000000UL ...     999999999999999UL: return 15;
  	case     1000000000000000UL ...    9999999999999999UL: return 16;
  	case    10000000000000000UL ...   99999999999999999UL: return 17;
  	case   100000000000000000UL ...  999999999999999999UL: return 18;
  	case  1000000000000000000UL ... 9999999999999999999UL: return 19; // this one
  	case 10000000000000000000UL ...             ULONG_MAX: return 20;
  	}
  	return 0;
  }

  int main(int argc, char **argv)
  {
  	unsigned long v = strtoul(argc > 1 ? argv[1] : "1111", NULL, 0);
  	printf("%lu : %d\n", v, nbdg(v));
  	return 0;
  }

  $ tcc dg.c
  dg.c:26: warning: empty case range
  $ x="";for i in 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0; do x=$x$i; ./a.out $x;done
  1 : 1
  12 : 2
  123 : 3
  1234 : 4
  12345 : 5
  123456 : 6
  1234567 : 7
  12345678 : 8
  123456789 : 9
  1234567890 : 10
  12345678901 : 11
  123456789012 : 12
  1234567890123 : 13
  12345678901234 : 14
  123456789012345 : 15
  1234567890123456 : 16
  12345678901234567 : 17
  123456789012345678 : 18
  1234567890123456789 : 0
  12345678901234567890 : 20

What this patch does is to use a separate set of signed and unsigned
case_cmp functions depending on whether the expression is signed or
unsigned, and also does this to decide when to emit the warning.

The bad code on output was caused by the removal of the unsigned bit
resulting from the signed sort, which causes only signed comparisons
to be emitted in the asm code. As such some sets could not match.

Note that there is no way to rely on the values only to sort properly
nor to emit the warning because we're effectively dealing with 65-bit
arithmetic here and any two values will have a different behavior
depending on the signed or unsigned expectation.

For unsigned expressions now the warning only happens when bounds are
switched, For signed expressions (e.g. if the input is signed long
above), the warning remains and the abnormal output as well. In both
cases this remains consistent with what gcc produces.
2020-08-18 11:27:27 +02:00
examples makefile: unify cross with native builds 2017-02-25 12:51:04 +01:00
include Add L suffix to LDBL values. 2020-07-16 07:59:34 +02:00
lib Add attribute bound_no_checking 2020-08-13 11:19:11 +02:00
tests Update attribute bound_no_checking 2020-08-14 06:35:47 +02:00
win32 rm helper scripts newly added by me 2020-08-16 10:46:19 +08:00
.gitignore OSX: make libtcc.dylib 2020-03-21 23:57:00 +08:00
arm64-gen.c Faster load/store arm64 2020-07-30 09:26:20 +02:00
arm64-link.c Add arm64 dll support 2020-08-01 19:44:49 +02:00
arm-asm.c allow libtcc states to be used concurrently 2019-12-11 02:36:19 +01:00
arm-gen.c Move bound functions to tccgen.c 2020-07-12 10:55:40 +02:00
arm-link.c Add arm dll support 2020-08-04 09:15:42 +02:00
c67-gen.c tccgen.c: cleanup debug support 2020-05-11 11:41:56 +02:00
c67-link.c allow libtcc states to be used concurrently 2019-12-11 02:36:19 +01:00
Changelog 'long' review 2017-09-24 18:57:48 +02:00
CodingStyle CodingStyle: Remove reference to misaligned struct CString. 2016-01-06 19:09:28 +00:00
coff.h Spelling fixes in C comments only 2017-05-07 21:38:09 -07:00
configure some cleanups related to recent commits 2020-07-06 13:00:47 +02:00
conftest.c some cleanups related to recent commits 2020-07-06 13:00:47 +02:00
COPYING changed license to LGPL 2003-05-24 14:18:56 +00:00
elf.h riscv64: Add skeleton target 2019-08-14 18:18:46 +02:00
i386-asm.c __builtin_/__bound_: A 'stay tiny' approach to the matter 2020-07-06 13:42:02 +02:00
i386-asm.h x86-asm: Fix lar opcode operands 2016-12-15 17:47:08 +01:00
i386-gen.c Move bound functions to tccgen.c 2020-07-12 10:55:40 +02:00
i386-link.c Update bound checking code. 2020-01-15 08:53:19 +01:00
i386-tok.h x86-64-asm: Support high registers %r8 - %r15 2016-12-15 17:47:09 +01:00
il-gen.c Spelling fixes in C comments only 2017-05-07 21:38:09 -07:00
il-opcodes.h Revert all of my changes to directories & codingstyle. 2015-07-29 16:57:12 -04:00
libtcc.c Add -C gcc compatible option which does currently nothing. This allows, among others, to compile gnumake from git ROOTB. 2020-07-11 06:41:44 +02:00
libtcc.h libtcc: accept tcc_define_symbol(s1, "sym=value", NULL) 2020-07-06 13:00:47 +02:00
Makefile add "libtcc.osx" entry to Makefile, for programs who need more pure libtcc.dylib without "@rpath/" config 2020-08-07 21:10:39 +08:00
README README: Fix typo and remove trailing whitespace 2019-09-14 15:37:20 +02:00
RELICENSING Add note about native Windows bootstrap using Cygwin. 2017-02-23 06:45:26 +01:00
riscv64-asm.c Add bound checking to arm, arm64 and riscv64 2020-06-16 07:39:48 +02:00
riscv64-gen.c riscv64: Fix a corner case 2020-07-15 21:47:39 +02:00
riscv64-link.c Add riscv dll support 2020-08-04 10:36:47 +02:00
stab.def Revert all of my changes to directories & codingstyle. 2015-07-29 16:57:12 -04:00
stab.h Revert all of my changes to directories & codingstyle. 2015-07-29 16:57:12 -04:00
tcc-doc.texi Fix typo in tcc-doc 2020-08-14 22:54:51 +01:00
tcc.c Add -C gcc compatible option which does currently nothing. This allows, among others, to compile gnumake from git ROOTB. 2020-07-11 06:41:44 +02:00
tcc.h Add attribute bound_no_checking 2020-08-13 11:19:11 +02:00
tccasm.c some cleanups related to recent commits 2020-07-06 13:00:47 +02:00
tcccoff.c allow libtcc states to be used concurrently 2019-12-11 02:36:19 +01:00
tccelf.c Fix dll on arm. 2020-08-05 13:55:11 +02:00
tccgen.c Fix switch/case on uint64_t 2020-08-18 11:27:27 +02:00
tcclib.h Revert all of my changes to directories & codingstyle. 2015-07-29 16:57:12 -04:00
tccmacho.c macos: initialize macho struct with memset which removes a clang warning on macOS. 2020-07-07 07:47:48 +02:00
tccpe.c rework leading underscores 2020-07-06 13:00:47 +02:00
tccpp.c Fix bounds checking 2020-07-07 21:10:51 +02:00
tccrun.c riscv64: Work around qemu bug 2020-07-15 23:11:58 +02:00
tcctok.h Update attribute bound_no_checking 2020-08-14 06:35:47 +02:00
tcctools.c tcc -MD: drop system includes and duplicates 2020-06-17 18:01:40 +02:00
texi2pod.pl Revert all of my changes to directories & codingstyle. 2015-07-29 16:57:12 -04:00
TODO Remove a bit-field TODO 2017-04-29 22:09:10 +02:00
USES USES: add mpc library 2020-07-11 20:00:37 +02:00
VERSION update VERSION to 0.9.27 2017-02-08 19:56:15 +01:00
x86_64-asm.h x86-64-asm: Fix mov im64,rax encoding 2017-02-23 00:16:25 +01:00
x86_64-gen.c Move bound functions to tccgen.c 2020-07-12 10:55:40 +02:00
x86_64-link.c rework leading underscores 2020-07-06 13:00:47 +02:00

Tiny C Compiler - C Scripting Everywhere - The Smallest ANSI C compiler
-----------------------------------------------------------------------

Features:
--------

- SMALL! You can compile and execute C code everywhere, for example on
  rescue disks.

- FAST! tcc generates optimized x86 code. No byte code
  overhead. Compile, assemble and link about 7 times faster than 'gcc
  -O0'.

- UNLIMITED! Any C dynamic library can be used directly. TCC is
  heading toward full ISOC99 compliance. TCC can of course compile
  itself.

- SAFE! tcc includes an optional memory and bound checker. Bound
  checked code can be mixed freely with standard code.

- Compile and execute C source directly. No linking or assembly
  necessary. Full C preprocessor included.

- C script supported : just add '#!/usr/local/bin/tcc -run' at the first
  line of your C source, and execute it directly from the command
  line.

Documentation:
-------------

1) Installation on a i386/x86_64/arm Linux/OSX/FreeBSD host

   ./configure
   make
   make test
   make install

   Notes: For OSX and FreeBSD, gmake should be used instead of make.
   For Windows read tcc-win32.txt.

makeinfo must be installed to compile the doc.  By default, tcc is
installed in /usr/local/bin.  ./configure --help  shows configuration
options.


2) Introduction

We assume here that you know ANSI C. Look at the example ex1.c to know
what the programs look like.

The include file <tcclib.h> can be used if you want a small basic libc
include support (especially useful for floppy disks). Of course, you
can also use standard headers, although they are slower to compile.

You can begin your C script with '#!/usr/local/bin/tcc -run' on the first
line and set its execute bits (chmod a+x your_script). Then, you can
launch the C code as a shell or perl script :-) The command line
arguments are put in 'argc' and 'argv' of the main functions, as in
ANSI C.

3) Examples

ex1.c: simplest example (hello world). Can also be launched directly
as a script: './ex1.c'.

ex2.c: more complicated example: find a number with the four
operations given a list of numbers (benchmark).

ex3.c: compute fibonacci numbers (benchmark).

ex4.c: more complicated: X11 program. Very complicated test in fact
because standard headers are being used ! As for ex1.c, can also be launched
directly as a script: './ex4.c'.

ex5.c: 'hello world' with standard glibc headers.

tcc.c: TCC can of course compile itself. Used to check the code
generator.

tcctest.c: auto test for TCC which tests many subtle possible bugs. Used
when doing 'make test'.

4) Full Documentation

Please read tcc-doc.html to have all the features of TCC.

Additional information is available for the Windows port in tcc-win32.txt.

License:
-------

TCC is distributed under the GNU Lesser General Public License (see
COPYING file).

Fabrice Bellard.