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llvm-project/llvm/test/Transforms/InstCombine/bitcast-store.ll

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Fix a case where instcombine was stripping metadata (and alignment) from stores when folding in bitcasts. llvm-svn: 117265
2010-10-26 00:16:27 +08:00
; RUN: opt -S -instcombine < %s | FileCheck %s
; Instcombine should preserve metadata and alignment while
; folding a bitcast into a store.
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"
%struct.A = type { i32 (...)** }
@G = external constant [5 x i8*]
[InstCombine] Don't fold bitcast into store if it would need addrspacecast Summary: Previously the code didn't check if the before and after types for the store were pointers to different address spaces. This resulted in instcombine using a bitcast to convert between pointers to different address spaces, causing an assertion due to the invalid cast. It is not be appropriate to use addrspacecast this case because it is not guaranteed to be a no-op cast. Instead bail out and do not do the transformation. CC: llvm-commits Differential Revision: http://llvm-reviews.chandlerc.com/D3117 llvm-svn: 204733
2014-03-26 01:21:41 +08:00
; CHECK-LABEL: @foo
[InstCombine] Change LLVM To canonicalize toward the value type being stored rather than the pointer type. This change is analogous to r220138 which changed the canonicalization for loads. The rationale is the same: memory does not have a type, operations (and thus the values they produce) have a type. We should match that type as closely as possible rather than reading some form of semantics into the pointer type. With this change, loads and stores should no longer be made with nonsensical types for the values that tehy load and store. This is particularly important when trying to match specific loaded and stored types in the process of doing other instcombines, which is what led me down this twisty maze of miscanonicalization. I've put quite some effort into looking through IR to find places where LLVM's optimizer was being unreasonably conservative in the face of mismatched load and store types, however it is possible (let's say, likely!) I have missed some. If you see regressions here, or from r220138, the likely cause is some part of LLVM failing to cope with load and store types differing. Test cases appreciated, it is important that we root all of these out of LLVM. llvm-svn: 222748
2014-11-25 18:09:51 +08:00
; CHECK: store i32 %x, i32* %{{.*}}, align 16, !noalias !0
define void @foo(i32 %x, float* %p) nounwind {
Fix a case where instcombine was stripping metadata (and alignment) from stores when folding in bitcasts. llvm-svn: 117265
2010-10-26 00:16:27 +08:00
entry:
[InstCombine] Change LLVM To canonicalize toward the value type being stored rather than the pointer type. This change is analogous to r220138 which changed the canonicalization for loads. The rationale is the same: memory does not have a type, operations (and thus the values they produce) have a type. We should match that type as closely as possible rather than reading some form of semantics into the pointer type. With this change, loads and stores should no longer be made with nonsensical types for the values that tehy load and store. This is particularly important when trying to match specific loaded and stored types in the process of doing other instcombines, which is what led me down this twisty maze of miscanonicalization. I've put quite some effort into looking through IR to find places where LLVM's optimizer was being unreasonably conservative in the face of mismatched load and store types, however it is possible (let's say, likely!) I have missed some. If you see regressions here, or from r220138, the likely cause is some part of LLVM failing to cope with load and store types differing. Test cases appreciated, it is important that we root all of these out of LLVM. llvm-svn: 222748
2014-11-25 18:09:51 +08:00
%x.cast = bitcast i32 %x to float
store float %x.cast, float* %p, align 16, !noalias !0
Fix a case where instcombine was stripping metadata (and alignment) from stores when folding in bitcasts. llvm-svn: 117265
2010-10-26 00:16:27 +08:00
ret void
}
[InstCombine] Don't fold bitcast into store if it would need addrspacecast Summary: Previously the code didn't check if the before and after types for the store were pointers to different address spaces. This resulted in instcombine using a bitcast to convert between pointers to different address spaces, causing an assertion due to the invalid cast. It is not be appropriate to use addrspacecast this case because it is not guaranteed to be a no-op cast. Instead bail out and do not do the transformation. CC: llvm-commits Differential Revision: http://llvm-reviews.chandlerc.com/D3117 llvm-svn: 204733
2014-03-26 01:21:41 +08:00
; Check instcombine doesn't try and fold the following bitcast into the store.
; This transformation would not be safe since we would need to use addrspacecast
; and addrspacecast is not guaranteed to be a no-op cast.
; CHECK-LABEL: @bar
; CHECK: %cast = bitcast i8** %b to i8 addrspace(1)**
; CHECK: store i8 addrspace(1)* %a, i8 addrspace(1)** %cast
define void @bar(i8 addrspace(1)* %a, i8** %b) nounwind {
entry:
%cast = bitcast i8** %b to i8 addrspace(1)**
store i8 addrspace(1)* %a, i8 addrspace(1)** %cast
ret void
}
IR: Make metadata typeless in assembly Now that `Metadata` is typeless, reflect that in the assembly. These are the matching assembly changes for the metadata/value split in r223802. - Only use the `metadata` type when referencing metadata from a call intrinsic -- i.e., only when it's used as a `Value`. - Stop pretending that `ValueAsMetadata` is wrapped in an `MDNode` when referencing it from call intrinsics. So, assembly like this: define @foo(i32 %v) { call void @llvm.foo(metadata !{i32 %v}, metadata !0) call void @llvm.foo(metadata !{i32 7}, metadata !0) call void @llvm.foo(metadata !1, metadata !0) call void @llvm.foo(metadata !3, metadata !0) call void @llvm.foo(metadata !{metadata !3}, metadata !0) ret void, !bar !2 } !0 = metadata !{metadata !2} !1 = metadata !{i32* @global} !2 = metadata !{metadata !3} !3 = metadata !{} turns into this: define @foo(i32 %v) { call void @llvm.foo(metadata i32 %v, metadata !0) call void @llvm.foo(metadata i32 7, metadata !0) call void @llvm.foo(metadata i32* @global, metadata !0) call void @llvm.foo(metadata !3, metadata !0) call void @llvm.foo(metadata !{!3}, metadata !0) ret void, !bar !2 } !0 = !{!2} !1 = !{i32* @global} !2 = !{!3} !3 = !{} I wrote an upgrade script that handled almost all of the tests in llvm and many of the tests in cfe (even handling many `CHECK` lines). I've attached it (or will attach it in a moment if you're speedy) to PR21532 to help everyone update their out-of-tree testcases. This is part of PR21532. llvm-svn: 224257
2014-12-16 03:07:53 +08:00
!0 = !{!0}