llvm/test/Transforms/InstCombine/narrow-switch.ll
Bruno Cardoso Lopes 06833ca7c1 Reapply: [InstCombine] Fix visitSwitchInst to use right operand types for sub cstexpr
The visitSwitchInst generates SUB constant expressions to recompute the
switch condition. When truncating the condition to a smaller type, SUB
expressions should use the previous type (before trunc) for both
operands. Also, fix code to also return the modified switch when only
the truncation is performed.

This fixes an assertion crash.

Differential Revision: http://reviews.llvm.org/D6644

rdar://problem/19191835

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224588 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-19 17:12:35 +00:00

124 lines
2.5 KiB
LLVM

; RUN: opt < %s -instcombine -S | FileCheck %s
target datalayout = "e-m:o-p:32:32-f64:32:64-v64:32:64-v128:32:128-a:0:32-n32-S32"
; CHECK-LABEL: define i32 @positive1
; CHECK: switch i32
; CHECK: i32 10, label
; CHECK: i32 100, label
; CHECK: i32 1001, label
define i32 @positive1(i64 %a) {
entry:
%and = and i64 %a, 4294967295
switch i64 %and, label %sw.default [
i64 10, label %return
i64 100, label %sw.bb1
i64 1001, label %sw.bb2
]
sw.bb1:
br label %return
sw.bb2:
br label %return
sw.default:
br label %return
return:
%retval.0 = phi i32 [ 24, %sw.default ], [ 123, %sw.bb2 ], [ 213, %sw.bb1 ], [ 231, %entry ]
ret i32 %retval.0
}
; CHECK-LABEL: define i32 @negative1
; CHECK: switch i32
; CHECK: i32 -10, label
; CHECK: i32 -100, label
; CHECK: i32 -1001, label
define i32 @negative1(i64 %a) {
entry:
%or = or i64 %a, -4294967296
switch i64 %or, label %sw.default [
i64 -10, label %return
i64 -100, label %sw.bb1
i64 -1001, label %sw.bb2
]
sw.bb1:
br label %return
sw.bb2:
br label %return
sw.default:
br label %return
return:
%retval.0 = phi i32 [ 24, %sw.default ], [ 123, %sw.bb2 ], [ 213, %sw.bb1 ], [ 231, %entry ]
ret i32 %retval.0
}
; Make sure truncating a constant int larger than 64-bit doesn't trigger an
; assertion.
; CHECK-LABEL: define i32 @trunc72to68
; CHECK: switch i68
; CHECK: i68 10, label
; CHECK: i68 100, label
; CHECK: i68 1001, label
define i32 @trunc72to68(i72 %a) {
entry:
%and = and i72 %a, 295147905179352825855
switch i72 %and, label %sw.default [
i72 10, label %return
i72 100, label %sw.bb1
i72 1001, label %sw.bb2
]
sw.bb1:
br label %return
sw.bb2:
br label %return
sw.default:
br label %return
return:
%retval.0 = phi i32 [ 24, %sw.default ], [ 123, %sw.bb2 ], [ 213, %sw.bb1 ], [ 231, %entry ]
ret i32 %retval.0
}
; Make sure to avoid assertion crashes and use the type before
; truncation to generate the sub constant expressions that leads
; to the recomputed condition.
;
; CHECK-LABEL: @trunc64to59
; CHECK: switch i59
; CHECK: i59 0, label
; CHECK: i59 18717182647723699, label
define void @trunc64to59(i64 %a) {
entry:
%tmp0 = and i64 %a, 15
%tmp1 = mul i64 %tmp0, -6425668444178048401
%tmp2 = add i64 %tmp1, 5170979678563097242
%tmp3 = mul i64 %tmp2, 1627972535142754813
switch i64 %tmp3, label %sw.default [
i64 847514119312061490, label %sw.bb1
i64 866231301959785189, label %sw.bb2
]
sw.bb1:
br label %sw.default
sw.bb2:
br label %sw.default
sw.default:
ret void
}