LLVM backend for 6502
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Chris Lattner 934520a747 Recursively scan scev expressions for common subexpressions. This allows us
to handle nested loops much better, for example, by being able to tell that
these two expressions:

{( 8 + ( 16 * ( 1 +  %Tmp11 +  %Tmp12)) +  %c_),+,( 16 *  %Tmp 12)}<loopentry.1>

{(( 16 * ( 1 +  %Tmp11 +  %Tmp12)) +  %c_),+,( 16 *  %Tmp12)}<loopentry.1>

Have the following common part that can be shared:
{(( 16 * ( 1 +  %Tmp11 +  %Tmp12)) +  %c_),+,( 16 *  %Tmp12)}<loopentry.1>

This allows us to codegen an important inner loop in 168.wupwise as:

.LBB_foo_4:     ; no_exit.1
        lfd f2, 16(r9)
        fmul f3, f0, f2
        fmul f2, f1, f2
        fadd f4, f3, f2
        stfd f4, 8(r9)
        fsub f2, f3, f2
        stfd f2, 16(r9)
        addi r8, r8, 1
        addi r9, r9, 16
        cmpw cr0, r8, r4
        ble .LBB_foo_4  ; no_exit.1

instead of:

.LBB_foo_3:     ; no_exit.1
        lfdx f2, r6, r9
        add r10, r6, r9
        lfd f3, 8(r10)
        fmul f4, f1, f2
        fmadd f4, f0, f3, f4
        stfd f4, 8(r10)
        fmul f3, f1, f3
        fmsub f2, f0, f2, f3
        stfdx f2, r6, r9
        addi r9, r9, 16
        addi r8, r8, 1
        cmpw cr0, r8, r4
        ble .LBB_foo_3  ; no_exit.1


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@22781 91177308-0d34-0410-b5e6-96231b3b80d8
2005-08-13 07:27:18 +00:00
autoconf Fix PR608: 2005-07-27 21:58:38 +00:00
docs Update a doc, patch contributed by Jim Laskey! 2005-08-02 19:14:25 +00:00
examples Eliminate all remaining tabs and trailing spaces. 2005-07-27 06:12:32 +00:00
include/llvm Remove an unncessary argument to SimplifySelectCC and add an additional 2005-08-13 06:14:17 +00:00
lib Recursively scan scev expressions for common subexpressions. This allows us 2005-08-13 07:27:18 +00:00
projects oops 2005-07-05 16:36:18 +00:00
runtime Remove trailing whitespace 2005-04-21 23:48:37 +00:00
test Added test cases to guarantee use of ORC and ANDC. 2005-08-12 23:40:14 +00:00
tools If the user interrupts bugpoint, don't extract loops 2005-08-02 23:25:56 +00:00
utils make is the standard name, not gmake 2005-08-02 00:10:52 +00:00
win32 Fix VC++ build problems. 2005-07-30 18:22:27 +00:00
Xcode First rev of Xcode 2.1 project 2005-08-11 22:19:26 +00:00
.cvsignore Ignore the configure.out file generated by "make reconfigure" 2005-06-18 23:01:25 +00:00
configure Fix PR608: 2005-07-27 21:58:38 +00:00
CREDITS.TXT Add a note, people are responsible for requesting that they be added to the 2005-08-02 22:10:21 +00:00
LICENSE.TXT Remove extraneous colons after program names for consistency 2005-05-12 21:39:01 +00:00
llvm.spec Onward to LLVM-1.6 and beyond! 2005-05-18 20:23:20 +00:00
llvm.spec.in Onward to LLVM-1.6 and beyond! 2005-05-18 20:23:20 +00:00
Makefile Make sure the tools get built if no build target is specified. 2005-05-29 00:49:24 +00:00
Makefile.common Update comments to reflect new variable names. Patch contributed by 2005-02-14 16:02:19 +00:00
Makefile.config.in Two changes: 2005-04-22 17:14:14 +00:00
Makefile.rules Fix oversized GOT problem with gcc-4 on alpha 2005-08-13 05:09:50 +00:00
README.txt

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

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