llvm-6502/test/Transforms/InstCombine/merge-icmp.ll
Benjamin Kramer 264ac878b2 InstCombine: Merge "(trunc x) == C1 & (and x, CA) == C2" into a single and+icmp.
This happens when GVN widens loads. Part of PR6627.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@130405 91177308-0d34-0410-b5e6-96231b3b80d8
2011-04-28 16:58:40 +00:00

30 lines
710 B
LLVM

; RUN: opt -S -instcombine < %s | FileCheck %s
define i1 @test1(i16* %x) {
%load = load i16* %x, align 4
%trunc = trunc i16 %load to i8
%cmp1 = icmp eq i8 %trunc, 127
%and = and i16 %load, -256
%cmp2 = icmp eq i16 %and, 17664
%or = and i1 %cmp1, %cmp2
ret i1 %or
; CHECK: @test1
; CHECK-NEXT: load i16
; CHECK-NEXT: icmp eq i16 %load, 17791
; CHECK-NEXT: ret i1
}
define i1 @test2(i16* %x) {
%load = load i16* %x, align 4
%and = and i16 %load, -256
%cmp1 = icmp eq i16 %and, 32512
%trunc = trunc i16 %load to i8
%cmp2 = icmp eq i8 %trunc, 69
%or = and i1 %cmp1, %cmp2
ret i1 %or
; CHECK: @test2
; CHECK-NEXT: load i16
; CHECK-NEXT: icmp eq i16 %load, 32581
; CHECK-NEXT: ret i1
}