llvm/test/Transforms/InstCombine/range-check.ll
Erik Eckstein 10e28ca6b1 InstCombine: simplify signed range checks
Try to convert two compares of a signed range check into a single unsigned compare.
Examples:
(icmp sge x, 0) & (icmp slt x, n) --> icmp ult x, n
(icmp slt x, 0) | (icmp sgt x, n) --> icmp ugt x, n




git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223224 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-03 10:39:15 +00:00

160 lines
3.7 KiB
LLVM

; RUN: opt < %s -instcombine -S | FileCheck %s
; Check simplification of
; (icmp sgt x, -1) & (icmp sgt/sge n, x) --> icmp ugt/uge n, x
; CHECK-LABEL: define i1 @test_and1
; CHECK: [[R:%[0-9]+]] = icmp ugt i32 %nn, %x
; CHECK: ret i1 [[R]]
define i1 @test_and1(i32 %x, i32 %n) {
%nn = and i32 %n, 2147483647
%a = icmp sge i32 %x, 0
%b = icmp slt i32 %x, %nn
%c = and i1 %a, %b
ret i1 %c
}
; CHECK-LABEL: define i1 @test_and2
; CHECK: [[R:%[0-9]+]] = icmp uge i32 %nn, %x
; CHECK: ret i1 [[R]]
define i1 @test_and2(i32 %x, i32 %n) {
%nn = and i32 %n, 2147483647
%a = icmp sgt i32 %x, -1
%b = icmp sle i32 %x, %nn
%c = and i1 %a, %b
ret i1 %c
}
; CHECK-LABEL: define i1 @test_and3
; CHECK: [[R:%[0-9]+]] = icmp ugt i32 %nn, %x
; CHECK: ret i1 [[R]]
define i1 @test_and3(i32 %x, i32 %n) {
%nn = and i32 %n, 2147483647
%a = icmp sgt i32 %nn, %x
%b = icmp sge i32 %x, 0
%c = and i1 %a, %b
ret i1 %c
}
; CHECK-LABEL: define i1 @test_and4
; CHECK: [[R:%[0-9]+]] = icmp uge i32 %nn, %x
; CHECK: ret i1 [[R]]
define i1 @test_and4(i32 %x, i32 %n) {
%nn = and i32 %n, 2147483647
%a = icmp sge i32 %nn, %x
%b = icmp sge i32 %x, 0
%c = and i1 %a, %b
ret i1 %c
}
; CHECK-LABEL: define i1 @test_or1
; CHECK: [[R:%[0-9]+]] = icmp ule i32 %nn, %x
; CHECK: ret i1 [[R]]
define i1 @test_or1(i32 %x, i32 %n) {
%nn = and i32 %n, 2147483647
%a = icmp slt i32 %x, 0
%b = icmp sge i32 %x, %nn
%c = or i1 %a, %b
ret i1 %c
}
; CHECK-LABEL: define i1 @test_or2
; CHECK: [[R:%[0-9]+]] = icmp ult i32 %nn, %x
; CHECK: ret i1 [[R]]
define i1 @test_or2(i32 %x, i32 %n) {
%nn = and i32 %n, 2147483647
%a = icmp sle i32 %x, -1
%b = icmp sgt i32 %x, %nn
%c = or i1 %a, %b
ret i1 %c
}
; CHECK-LABEL: define i1 @test_or3
; CHECK: [[R:%[0-9]+]] = icmp ule i32 %nn, %x
; CHECK: ret i1 [[R]]
define i1 @test_or3(i32 %x, i32 %n) {
%nn = and i32 %n, 2147483647
%a = icmp sle i32 %nn, %x
%b = icmp slt i32 %x, 0
%c = or i1 %a, %b
ret i1 %c
}
; CHECK-LABEL: define i1 @test_or4
; CHECK: [[R:%[0-9]+]] = icmp ult i32 %nn, %x
; CHECK: ret i1 [[R]]
define i1 @test_or4(i32 %x, i32 %n) {
%nn = and i32 %n, 2147483647
%a = icmp slt i32 %nn, %x
%b = icmp slt i32 %x, 0
%c = or i1 %a, %b
ret i1 %c
}
; Negative tests
; CHECK-LABEL: define i1 @negative1
; CHECK: %a = icmp
; CHECK: %b = icmp
; CHECK: %c = and i1 %a, %b
; CHECK: ret i1 %c
define i1 @negative1(i32 %x, i32 %n) {
%nn = and i32 %n, 2147483647
%a = icmp slt i32 %x, %nn
%b = icmp sgt i32 %x, 0 ; should be: icmp sge
%c = and i1 %a, %b
ret i1 %c
}
; CHECK-LABEL: define i1 @negative2
; CHECK: %a = icmp
; CHECK: %b = icmp
; CHECK: %c = and i1 %a, %b
; CHECK: ret i1 %c
define i1 @negative2(i32 %x, i32 %n) {
%a = icmp slt i32 %x, %n ; n can be negative
%b = icmp sge i32 %x, 0
%c = and i1 %a, %b
ret i1 %c
}
; CHECK-LABEL: define i1 @negative3
; CHECK: %a = icmp
; CHECK: %b = icmp
; CHECK: %c = and i1 %a, %b
; CHECK: ret i1 %c
define i1 @negative3(i32 %x, i32 %y, i32 %n) {
%nn = and i32 %n, 2147483647
%a = icmp slt i32 %x, %nn
%b = icmp sge i32 %y, 0 ; should compare %x and not %y
%c = and i1 %a, %b
ret i1 %c
}
; CHECK-LABEL: define i1 @negative4
; CHECK: %a = icmp
; CHECK: %b = icmp
; CHECK: %c = and i1 %a, %b
; CHECK: ret i1 %c
define i1 @negative4(i32 %x, i32 %n) {
%nn = and i32 %n, 2147483647
%a = icmp ne i32 %x, %nn ; should be: icmp slt/sle
%b = icmp sge i32 %x, 0
%c = and i1 %a, %b
ret i1 %c
}
; CHECK-LABEL: define i1 @negative5
; CHECK: %a = icmp
; CHECK: %b = icmp
; CHECK: %c = or i1 %a, %b
; CHECK: ret i1 %c
define i1 @negative5(i32 %x, i32 %n) {
%nn = and i32 %n, 2147483647
%a = icmp slt i32 %x, %nn
%b = icmp sge i32 %x, 0
%c = or i1 %a, %b ; should be: and
ret i1 %c
}