| ; RUN: opt -S < %s -instcombine | FileCheck %s |
| |
| target datalayout = "e-p1:16:16-p2:32:32-p3:64:64" |
| |
| @G1 = global i32 42, align 1 |
| @G2 = global i32 42 |
| @G3 = global [4 x i8] zeroinitializer, align 1 |
| |
| @A1 = alias i32, bitcast (i8* getelementptr inbounds ([4 x i8], [4 x i8]* @G3, i32 0, i32 2) to i32*) |
| @A2 = alias i32, inttoptr (i64 and (i64 ptrtoint (i8* getelementptr inbounds ([4 x i8], [4 x i8]* @G3, i32 0, i32 3) to i64), i64 -4) to i32*) |
| |
| define i64 @f1() { |
| ; This cannot be constant folded because G1 is underaligned. |
| ; CHECK-LABEL: @f1( |
| ; CHECK: ret i64 and |
| ret i64 and (i64 ptrtoint (i32* @G1 to i64), i64 1) |
| } |
| |
| define i64 @f2() { |
| ; The preferred alignment for G2 allows this one to foled to zero. |
| ; CHECK-LABEL: @f2( |
| ; CHECK: ret i64 0 |
| ret i64 and (i64 ptrtoint (i32* @G2 to i64), i64 1) |
| } |
| |
| define i64 @g1() { |
| ; This cannot be constant folded because A1 aliases G3 which is underalaigned. |
| ; CHECK-LABEL: @g1( |
| ; CHECK: ret i64 and |
| ret i64 and (i64 ptrtoint (i32* @A1 to i64), i64 1) |
| } |
| |
| define i64 @g2() { |
| ; While A2 also aliases G3 which is underaligned, the math of A2 forces a |
| ; certain alignment allowing this to fold to zero. |
| ; CHECK-LABEL: @g2( |
| ; CHECK: ret i64 0 |
| ret i64 and (i64 ptrtoint (i32* @A2 to i64), i64 1) |
| } |
| |