mirror of
https://github.com/RPCS3/llvm-mirror.git
synced 2024-11-01 00:12:50 +01:00
952bb51433
Patch from Preston Briggs <preston.briggs@gmail.com>.
This is an updated version of the dependence-analysis patch, including an MIV
test based on Banerjee's inequalities.
It's a fairly complete implementation of the paper
Practical Dependence Testing
Gina Goff, Ken Kennedy, and Chau-Wen Tseng
PLDI 1991
It cannot yet propagate constraints between coupled RDIV subscripts (discussed
in Section 5.3.2 of the paper).
It's organized as a FunctionPass with a single entry point that supports testing
for dependence between two instructions in a function. If there's no dependence,
it returns null. If there's a dependence, it returns a pointer to a Dependence
which can be queried about details (what kind of dependence, is it loop
independent, direction and distance vector entries, etc). I haven't included
every imaginable feature, but there's a good selection that should be adequate
for supporting many loop transformations. Of course, it can be extended as
necessary.
Included in the patch file are many test cases, commented with C code showing
the loops and array references.
llvm-svn: 165708
54 lines
1.5 KiB
LLVM
54 lines
1.5 KiB
LLVM
; RUN: opt < %s -analyze -basicaa -da | FileCheck %s
|
|
|
|
; ModuleID = 'ZIV.bc'
|
|
target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64-S128"
|
|
target triple = "x86_64-apple-macosx10.6.0"
|
|
|
|
|
|
;; A[n + 1] = ...
|
|
;; ... = A[1 + n];
|
|
|
|
define void @z0(i32* %A, i32* %B, i64 %n) nounwind uwtable ssp {
|
|
entry:
|
|
%add = add i64 %n, 1
|
|
%arrayidx = getelementptr inbounds i32* %A, i64 %add
|
|
store i32 0, i32* %arrayidx, align 4
|
|
%add1 = add i64 %n, 1
|
|
%arrayidx2 = getelementptr inbounds i32* %A, i64 %add1
|
|
%0 = load i32* %arrayidx2, align 4
|
|
; CHECK: da analyze - consistent flow!
|
|
store i32 %0, i32* %B, align 4
|
|
ret void
|
|
}
|
|
|
|
|
|
;; A[n] = ...
|
|
;; ... = A[n + 1];
|
|
|
|
define void @z1(i32* %A, i32* %B, i64 %n) nounwind uwtable ssp {
|
|
entry:
|
|
%arrayidx = getelementptr inbounds i32* %A, i64 %n
|
|
store i32 0, i32* %arrayidx, align 4
|
|
%add = add i64 %n, 1
|
|
%arrayidx1 = getelementptr inbounds i32* %A, i64 %add
|
|
%0 = load i32* %arrayidx1, align 4
|
|
; CHECK: da analyze - none!
|
|
store i32 %0, i32* %B, align 4
|
|
ret void
|
|
}
|
|
|
|
|
|
;; A[n] = ...
|
|
;; ... = A[m];
|
|
|
|
define void @z2(i32* %A, i32* %B, i64 %n, i64 %m) nounwind uwtable ssp {
|
|
entry:
|
|
%arrayidx = getelementptr inbounds i32* %A, i64 %n
|
|
store i32 0, i32* %arrayidx, align 4
|
|
%arrayidx1 = getelementptr inbounds i32* %A, i64 %m
|
|
%0 = load i32* %arrayidx1, align 4
|
|
; CHECK: da analyze - flow!
|
|
store i32 %0, i32* %B, align 4
|
|
ret void
|
|
}
|