llvm/test/Transforms/InstCombine/trunc.ll
Jakob Stoklund Olesen 7ee3ca10f5 Revert remaining part of r93200: "Disable folding sext(trunc(x)) -> x"
This fixes PR5997.

These transforms were disabled because codegen couldn't deal with other
uses of trunc(x). This is now handled by the peephole pass.

This causes no regressions on x86-64.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@159003 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-22 16:36:43 +00:00

121 lines
2.5 KiB
LLVM

; RUN: opt < %s -instcombine -S | FileCheck %s
target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64"
; Instcombine should be able to eliminate all of these ext casts.
declare void @use(i32)
define i64 @test1(i64 %a) {
%b = trunc i64 %a to i32
%c = and i32 %b, 15
%d = zext i32 %c to i64
call void @use(i32 %b)
ret i64 %d
; CHECK: @test1
; CHECK-NOT: ext
; CHECK: ret
}
define i64 @test2(i64 %a) {
%b = trunc i64 %a to i32
%c = shl i32 %b, 4
%q = ashr i32 %c, 4
%d = sext i32 %q to i64
call void @use(i32 %b)
ret i64 %d
; CHECK: @test2
; CHECK: shl i64 %a, 36
; CHECK: %d = ashr exact i64 {{.*}}, 36
; CHECK: ret i64 %d
}
define i64 @test3(i64 %a) {
%b = trunc i64 %a to i32
%c = and i32 %b, 8
%d = zext i32 %c to i64
call void @use(i32 %b)
ret i64 %d
; CHECK: @test3
; CHECK-NOT: ext
; CHECK: ret
}
define i64 @test4(i64 %a) {
%b = trunc i64 %a to i32
%c = and i32 %b, 8
%x = xor i32 %c, 8
%d = zext i32 %x to i64
call void @use(i32 %b)
ret i64 %d
; CHECK: @test4
; CHECK: = and i64 %a, 8
; CHECK: = xor i64 {{.*}}, 8
; CHECK-NOT: ext
; CHECK: ret
}
define i32 @test5(i32 %A) {
%B = zext i32 %A to i128
%C = lshr i128 %B, 16
%D = trunc i128 %C to i32
ret i32 %D
; CHECK: @test5
; CHECK: %C = lshr i32 %A, 16
; CHECK: ret i32 %C
}
define i32 @test6(i64 %A) {
%B = zext i64 %A to i128
%C = lshr i128 %B, 32
%D = trunc i128 %C to i32
ret i32 %D
; CHECK: @test6
; CHECK: %C = lshr i64 %A, 32
; CHECK: %D = trunc i64 %C to i32
; CHECK: ret i32 %D
}
define i92 @test7(i64 %A) {
%B = zext i64 %A to i128
%C = lshr i128 %B, 32
%D = trunc i128 %C to i92
ret i92 %D
; CHECK: @test7
; CHECK: %B = zext i64 %A to i92
; CHECK: %C = lshr i92 %B, 32
; CHECK: ret i92 %C
}
define i64 @test8(i32 %A, i32 %B) {
%tmp38 = zext i32 %A to i128
%tmp32 = zext i32 %B to i128
%tmp33 = shl i128 %tmp32, 32
%ins35 = or i128 %tmp33, %tmp38
%tmp42 = trunc i128 %ins35 to i64
ret i64 %tmp42
; CHECK: @test8
; CHECK: %tmp38 = zext i32 %A to i64
; CHECK: %tmp32 = zext i32 %B to i64
; CHECK: %tmp33 = shl nuw i64 %tmp32, 32
; CHECK: %ins35 = or i64 %tmp33, %tmp38
; CHECK: ret i64 %ins35
}
define i8 @test9(i32 %X) {
%Y = and i32 %X, 42
%Z = trunc i32 %Y to i8
ret i8 %Z
; CHECK: @test9
; CHECK: trunc
; CHECK: and
; CHECK: ret
}
; rdar://8808586
define i8 @test10(i32 %X) {
%Y = trunc i32 %X to i8
%Z = and i8 %Y, 42
ret i8 %Z
; CHECK: @test10
; CHECK: trunc
; CHECK: and
; CHECK: ret
}