119 lines
3.3 KiB
LLVM
119 lines
3.3 KiB
LLVM
; RUN: opt < %s -analyze -basicaa -lda | FileCheck %s
|
|
|
|
@x = common global [256 x i32] zeroinitializer, align 4
|
|
@y = common global [256 x i32] zeroinitializer, align 4
|
|
|
|
;; for (i = 0; i < 256; i++)
|
|
;; x[i] = x[255 - i] + y[i]
|
|
|
|
define void @f1(...) nounwind {
|
|
entry:
|
|
br label %for.body
|
|
|
|
for.body:
|
|
%i = phi i64 [ 0, %entry ], [ %i.next, %for.body ]
|
|
%i.255 = sub i64 255, %i
|
|
%y.ld.addr = getelementptr [256 x i32]* @y, i64 0, i64 %i
|
|
%x.ld.addr = getelementptr [256 x i32]* @x, i64 0, i64 %i.255
|
|
%x.st.addr = getelementptr [256 x i32]* @x, i64 0, i64 %i
|
|
%x = load i32* %x.ld.addr ; 0
|
|
%y = load i32* %y.ld.addr ; 1
|
|
%r = add i32 %y, %x
|
|
store i32 %r, i32* %x.st.addr ; 2
|
|
; CHECK: 0,2: dep
|
|
; CHECK: 1,2: ind
|
|
%i.next = add i64 %i, 1
|
|
%exitcond = icmp eq i64 %i.next, 256
|
|
br i1 %exitcond, label %for.end, label %for.body
|
|
|
|
for.end:
|
|
ret void
|
|
}
|
|
|
|
;; for (i = 0; i < 100; i++)
|
|
;; x[i] = x[255 - i] + y[i]
|
|
|
|
define void @f2(...) nounwind {
|
|
entry:
|
|
br label %for.body
|
|
|
|
for.body:
|
|
%i = phi i64 [ 0, %entry ], [ %i.next, %for.body ]
|
|
%i.255 = sub i64 255, %i
|
|
%y.ld.addr = getelementptr [256 x i32]* @y, i64 0, i64 %i
|
|
%x.ld.addr = getelementptr [256 x i32]* @x, i64 0, i64 %i.255
|
|
%x.st.addr = getelementptr [256 x i32]* @x, i64 0, i64 %i
|
|
%x = load i32* %x.ld.addr ; 0
|
|
%y = load i32* %y.ld.addr ; 1
|
|
%r = add i32 %y, %x
|
|
store i32 %r, i32* %x.st.addr ; 2
|
|
; CHECK: 0,2: dep
|
|
; CHECK: 1,2: ind
|
|
%i.next = add i64 %i, 1
|
|
%exitcond = icmp eq i64 %i.next, 100
|
|
br i1 %exitcond, label %for.end, label %for.body
|
|
|
|
for.end:
|
|
ret void
|
|
}
|
|
|
|
;; // the first iteration (i=0) leads to an out-of-bounds access of x. as the
|
|
;; // result of this access is undefined, _any_ dependence result is safe.
|
|
;; for (i = 0; i < 256; i++)
|
|
;; x[i] = x[256 - i] + y[i]
|
|
|
|
define void @f3(...) nounwind {
|
|
entry:
|
|
br label %for.body
|
|
|
|
for.body:
|
|
%i = phi i64 [ 0, %entry ], [ %i.next, %for.body ]
|
|
%i.256 = sub i64 0, %i
|
|
%y.ld.addr = getelementptr [256 x i32]* @y, i64 0, i64 %i
|
|
%x.ld.addr = getelementptr [256 x i32]* @x, i64 1, i64 %i.256
|
|
%x.st.addr = getelementptr [256 x i32]* @x, i64 0, i64 %i
|
|
%x = load i32* %x.ld.addr ; 0
|
|
%y = load i32* %y.ld.addr ; 1
|
|
%r = add i32 %y, %x
|
|
store i32 %r, i32* %x.st.addr ; 2
|
|
; CHECK: 0,2: dep
|
|
; CHECK: 1,2:
|
|
%i.next = add i64 %i, 1
|
|
%exitcond = icmp eq i64 %i.next, 256
|
|
br i1 %exitcond, label %for.end, label %for.body
|
|
|
|
for.end:
|
|
ret void
|
|
}
|
|
|
|
;; // slightly contrived but valid IR for the following loop, where all
|
|
;; // accesses in all iterations are within bounds. while this example's first
|
|
;; // (ZIV-)subscript is (0, 1), accesses are dependent.
|
|
;; for (i = 1; i < 256; i++)
|
|
;; x[i] = x[256 - i] + y[i]
|
|
|
|
define void @f4(...) nounwind {
|
|
entry:
|
|
br label %for.body
|
|
|
|
for.body:
|
|
%i = phi i64 [ 0, %entry ], [ %i.next, %for.body ]
|
|
%i.1 = add i64 1, %i
|
|
%i.256 = sub i64 -1, %i
|
|
%y.ld.addr = getelementptr [256 x i32]* @y, i64 0, i64 %i.1
|
|
%x.ld.addr = getelementptr [256 x i32]* @x, i64 1, i64 %i.256
|
|
%x.st.addr = getelementptr [256 x i32]* @x, i64 0, i64 %i.1
|
|
%x = load i32* %x.ld.addr ; 0
|
|
%y = load i32* %y.ld.addr ; 1
|
|
%r = add i32 %y, %x
|
|
store i32 %r, i32* %x.st.addr ; 2
|
|
; CHECK: 0,2: dep
|
|
; CHECK: 1,2: ind
|
|
%i.next = add i64 %i, 1
|
|
%exitcond = icmp eq i64 %i.next, 256
|
|
br i1 %exitcond, label %for.end, label %for.body
|
|
|
|
for.end:
|
|
ret void
|
|
}
|