mirror of
https://github.com/c64scene-ar/llvm-6502.git
synced 2025-04-07 16:42:07 +00:00
84734ce8ef
Changing 'op' here caused us to not enter the store into a map, causing
reemission of the code!! In practice, a simple loop like this:
no_exit: ; preds = %no_exit, %entry
%indvar = phi uint [ %indvar.next, %no_exit ], [ 0, %entry ] ; <uint> [#uses=3]
%tmp.4 = getelementptr "complex long double"* %P, uint %indvar, uint 0 ; <double*> [#uses=1]
store double 0.000000e+00, double* %tmp.4
%indvar.next = add uint %indvar, 1 ; <uint> [#uses=2]
%exitcond = seteq uint %indvar.next, %N ; <bool> [#uses=1]
br bool %exitcond, label %return, label %no_exit
was being code gen'd to:
.LBBtest_1: # no_exit
movl %edx, %esi
shll $4, %esi
movl $0, 4(%eax,%esi)
movl $0, (%eax,%esi)
incl %edx
movl $0, (%eax,%esi)
movl $0, 4(%eax,%esi)
cmpl %ecx, %edx
jne .LBBtest_1 # no_exit
Note that we are doing 4 32-bit stores instead of 2. Now we generate:
.LBBtest_1: # no_exit
movl %edx, %esi
incl %esi
shll $4, %edx
movl $0, (%eax,%edx)
movl $0, 4(%eax,%edx)
cmpl %ecx, %esi
movl %esi, %edx
jne .LBBtest_1 # no_exit
This is much happier, though it would be even better if the increment of ESI
was scheduled after the compare :-/
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@20265 91177308-0d34-0410-b5e6-96231b3b80d8
Low Level Virtual Machine (LLVM) ================================ This directory and its subdirectories contain source code for the Low Level Virtual Machine, a toolkit for the construction of highly optimized compilers, optimizers, and runtime environments. LLVM is open source software. You may freely distribute it under the terms of the license agreement found in LICENSE.txt. Please see the HTML documentation provided in docs/index.html for further assistance with LLVM.