llvm/test/Transforms/InstCombine/2010-03-03-ExtElim.ll
Nick Lewycky 5bf7f88ea2 Make the 'icmp pred trunc(ext(X)), CST --> icmp pred X, ext(trunc(CST))'
transformation much more careful. Truncating binary '01' to '1' sounds like it's
safe until you realize that it switched from positive to negative under a signed
interpretation, and that depends on the icmp predicate.

Also a few miscellaneous cleanups.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@97721 91177308-0d34-0410-b5e6-96231b3b80d8
2010-03-04 06:54:10 +00:00

19 lines
824 B
LLVM

; RUN: opt -instcombine -S %s | FileCheck %s
; PR6486
target datalayout = "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-a0:0:64-f80:32:32-n8:16:32"
target triple = "i386-unknown-linux-gnu"
@g_92 = common global [2 x i32*] zeroinitializer, align 4 ; <[2 x i32*]*> [#uses=1]
@g_177 = constant i32** bitcast (i8* getelementptr (i8* bitcast ([2 x i32*]* @g_92 to i8*), i64 4) to i32**), align 4 ; <i32***> [#uses=1]
define i1 @test() nounwind {
; CHECK: @test
%tmp = load i32*** @g_177 ; <i32**> [#uses=1]
%cmp = icmp ne i32** null, %tmp ; <i1> [#uses=1]
%conv = zext i1 %cmp to i32 ; <i32> [#uses=1]
%cmp1 = icmp sle i32 0, %conv ; <i1> [#uses=1]
ret i1 %cmp1
; CHECK: ret i1 true
}