Teach instruction simplify to use constant ranges to solve problems of the form

"icmp pred %X, CI" and a number of examples where "%X = binop %Y, CI2".

Some of these cases (div and rem) used to make it through opt -O2, but the
others are probably now making code elsewhere redundant (probably instcombine).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@126988 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Nick Lewycky
2011-03-04 07:00:57 +00:00
parent 86d822df6d
commit 3a73e343d0
2 changed files with 137 additions and 41 deletions

View File

@@ -137,22 +137,38 @@ define i1 @shl(i32 %x) {
; CHECK: ret i1 false
}
define i1 @lshr(i32 %x) {
; CHECK: @lshr
define i1 @lshr1(i32 %x) {
; CHECK: @lshr1
%s = lshr i32 -1, %x
%c = icmp eq i32 %s, 0
ret i1 %c
; CHECK: ret i1 false
}
define i1 @ashr(i32 %x) {
; CHECK: @ashr
define i1 @lshr2(i32 %x) {
; CHECK: @lshr2
%s = lshr i32 %x, 30
%c = icmp ugt i32 %s, 8
ret i1 %c
; CHECK: ret i1 false
}
define i1 @ashr1(i32 %x) {
; CHECK: @ashr1
%s = ashr i32 -1, %x
%c = icmp eq i32 %s, 0
ret i1 %c
; CHECK: ret i1 false
}
define i1 @ashr2(i32 %x) {
; CHECK: @ashr2
%s = ashr i32 %x, 30
%c = icmp slt i32 %s, -5
ret i1 %c
; CHECK: ret i1 false
}
define i1 @select1(i1 %cond) {
; CHECK: @select1
%s = select i1 %cond, i32 1, i32 0
@@ -203,3 +219,59 @@ define i1 @urem2(i32 %X, i32 %Y) {
ret i1 %B
; CHECK ret i1 false
}
define i1 @urem3(i32 %X) {
; CHECK: @urem3
%A = urem i32 %X, 10
%B = icmp ult i32 %A, 15
ret i1 %B
; CHECK: ret i1 true
}
define i1 @urem4(i32 %X) {
; CHECK: @urem4
%A = urem i32 %X, 15
%B = icmp ult i32 %A, 10
ret i1 %B
; CHECK: ret i1 %B
}
define i1 @srem1(i32 %X) {
; CHECK: @srem1
%A = srem i32 %X, -5
%B = icmp sgt i32 %A, 5
ret i1 %B
; CHECK: ret i1 false
}
define i1 @udiv1(i32 %X) {
; CHECK: @udiv1
%A = udiv i32 %X, 1000000
%B = icmp ult i32 %A, 5000
ret i1 %B
; CHECK: ret i1 true
}
define i1 @sdiv1(i32 %X) {
; CHECK: @sdiv1
%A = sdiv i32 %X, 1000000
%B = icmp slt i32 %A, 3000
ret i1 %B
; CHECK: ret i1 true
}
define i1 @or1(i32 %X) {
; CHECK: @or1
%A = or i32 %X, 62
%B = icmp ult i32 %A, 50
ret i1 %B
; CHECK: ret i1 false
}
define i1 @and1(i32 %X) {
; CHECK: @and1
%A = and i32 %X, 62
%B = icmp ugt i32 %A, 70
ret i1 %B
; CHECK: ret i1 false
}