LLVM backend for 6502
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Quentin Colombet 8201185d61 [X86] Custom lower UINT_TO_FP from v4f32 to v4i32, and for v8f32 to v8i32 if
AVX2 is available.
According to IACA, the new lowering has a throughput of 8 cycles instead of 13
with the previous one.

Althought this lowering kicks in some SPECs benchmarks, the performance
improvement was within the noise.

Correctness testing has been done for the whole range of uint32_t with the
following program:
    uint4 v = (uint4) {0,1,2,3};
    uint32_t i;
    
    //Check correctness over entire range for uint4 -> float4 conversion
    for( i = 0; i < 1U << (32-2); i++ )
    {
        float4 t = test(v);
        float4 c = correct(v);
        
        if( 0xf != _mm_movemask_ps( t == c ))
        {
            printf( "Error @ %vx: %vf vs. %vf\n", v, c, t);
            return -1;
        }
        
        v += 4;
    }
Where "correct" is the old lowering and "test" the new one.

The patch adds a test case for the two custom lowering instruction.
It also modifies the vector cost model, which is why cast.ll and uitofp.ll are
modified.
2009-02-26-MachineLICMBug.ll is also modified because we now hoist 7
instructions instead of 4 (3 more constant loads).

rdar://problem/18153096>


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221657 91177308-0d34-0410-b5e6-96231b3b80d8
2014-11-11 02:23:47 +00:00
autoconf Add a check for misbehaving -Wcomment from gcc-4.7 and add 2014-11-05 00:35:15 +00:00
bindings [OCaml] Fix mismatched CAMLparam/CAMLreturn. 2014-11-03 11:47:14 +00:00
cmake Pass PRIVATE to target_link_libraries if using shared libraries. 2014-11-07 15:33:56 +00:00
docs configure.ac lives in autoconf/, not autotools/ 2014-11-10 22:36:04 +00:00
examples [CMake] llvm/examples: Update libdeps for unoptimized builds. 2014-10-31 15:27:16 +00:00
include Fix variable names and comment style. NFC. 2014-11-10 16:31:06 +00:00
lib [X86] Custom lower UINT_TO_FP from v4f32 to v4i32, and for v8f32 to v8i32 if 2014-11-11 02:23:47 +00:00
projects
test [X86] Custom lower UINT_TO_FP from v4f32 to v4i32, and for v8f32 to v8i32 if 2014-11-11 02:23:47 +00:00
tools [CMake] llvm-c-test: Use libLLVM.so if it is available. 2014-11-10 15:04:26 +00:00
unittests [CMake] LLVMSupport: Give system_libs PRIVATE scope when LLVMSupport is built as SHARED. Users of LLVMSupport won't inherit ${system_libs}. 2014-11-07 16:08:19 +00:00
utils Use findProgramByName. 2014-11-04 01:29:59 +00:00
.arcconfig
.clang-format
.clang-tidy Enable display of compiler diagnostics in clang-tidy by default. 2014-10-29 17:29:38 +00:00
.gitignore Initial version of Go bindings. 2014-10-16 22:48:02 +00:00
CMakeLists.txt Pass PRIVATE to target_link_libraries if using shared libraries. 2014-11-07 15:33:56 +00:00
CODE_OWNERS.TXT Add Tom Stellard's role as 3.5 release manager. 2014-09-12 08:07:31 +00:00
configure Add a check for misbehaving -Wcomment from gcc-4.7 and add 2014-11-05 00:35:15 +00:00
CREDITS.TXT Rise from the dead and update personal info 2014-08-25 17:51:04 +00:00
LICENSE.TXT Remove projects/sample. 2014-03-12 22:40:22 +00:00
llvm.spec.in
LLVMBuild.txt Remove the very substantial, largely unmaintained legacy PGO 2013-10-02 15:42:23 +00:00
Makefile
Makefile.common
Makefile.config.in Add a check for misbehaving -Wcomment from gcc-4.7 and add 2014-11-05 00:35:15 +00:00
Makefile.rules Add a check for misbehaving -Wcomment from gcc-4.7 and add 2014-11-05 00:35:15 +00:00
README.txt

Low Level Virtual Machine (LLVM)
================================

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