Files
llvm-6502/test/Transforms/RewriteStatepointsForGC/liveness-basics.ll
Sanjoy Das 5b5782c20e [RewriteStatepointsForGC] Fix a bug on creating gc_relocate for pointer to vector of pointers
Summary:
In RewriteStatepointsForGC pass, we create a gc_relocate intrinsic for
each relocated pointer, and the gc_relocate has the same type with the
pointer. During the creation of gc_relocate intrinsic, llvm requires to
mangle its type. However, llvm does not support mangling of all possible
types. RewriteStatepointsForGC will hit an assertion failure when it
tries to create a gc_relocate for pointer to vector of pointers because
mangling for vector of pointers is not supported.

This patch changes the way RewriteStatepointsForGC pass creates
gc_relocate. For each relocated pointer, we erase the type of pointers
and create an unified gc_relocate of type i8 addrspace(1)*. Then a
bitcast is inserted to convert the gc_relocate to the correct type. In
this way, gc_relocate does not need to deal with different types of
pointers and the unsupported type mangling is no longer a problem. This
change would also ease further merge when LLVM erases types of pointers
and introduces an unified pointer type.

Some minor changes are also introduced to gc_relocate related part in
InstCombineCalls, CodeGenPrepare, and Verifier accordingly.

Patch by Chen Li!

Reviewers: reames, AndyAyers, sanjoy

Reviewed By: sanjoy

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D9592

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237009 91177308-0d34-0410-b5e6-96231b3b80d8
2015-05-11 18:49:34 +00:00

168 lines
5.6 KiB
LLVM

; A collection of liveness test cases to ensure we're reporting the
; correct live values at statepoints
; RUN: opt -rewrite-statepoints-for-gc -S < %s | FileCheck %s
; Tests to make sure we consider %obj live in both the taken and untaken
; predeccessor of merge.
define i64 addrspace(1)* @test1(i1 %cmp, i64 addrspace(1)* %obj) gc "statepoint-example" {
; CHECK-LABEL: @test1
entry:
br i1 %cmp, label %taken, label %untaken
taken:
; CHECK-LABEL: taken:
; CHECK-NEXT: gc.statepoint
; CHECK-NEXT: %obj.relocated = call coldcc i8 addrspace(1)*
; CHECK-NEXT: bitcast
; CHECK-NEXT: br label %merge
call i32 (void ()*, i32, i32, ...) @llvm.experimental.gc.statepoint.p0f_isVoidf(void ()* @foo, i32 0, i32 0, i32 0, i32 0)
br label %merge
untaken:
; CHECK-LABEL: untaken:
; CHECK-NEXT: gc.statepoint
; CHECK-NEXT: %obj.relocated1 = call coldcc i8 addrspace(1)*
; CHECK-NEXT: bitcast
; CHECK-NEXT: br label %merge
call i32 (void ()*, i32, i32, ...) @llvm.experimental.gc.statepoint.p0f_isVoidf(void ()* @foo, i32 0, i32 0, i32 0, i32 0)
br label %merge
merge:
; CHECK-LABEL: merge:
; CHECK-NEXT: %.0 = phi i64 addrspace(1)* [ %obj.relocated.casted, %taken ], [ %obj.relocated1.casted, %untaken ]
; CHECK-NEXT: ret i64 addrspace(1)* %.0
ret i64 addrspace(1)* %obj
}
; A local kill should not effect liveness in predecessor block
define i64 addrspace(1)* @test2(i1 %cmp, i64 addrspace(1)** %loc) gc "statepoint-example" {
; CHECK-LABEL: @test2
entry:
; CHECK-LABEL: entry:
; CHECK-NEXT: gc.statepoint
; CHECK-NEXT: br
call i32 (void ()*, i32, i32, ...) @llvm.experimental.gc.statepoint.p0f_isVoidf(void ()* @foo, i32 0, i32 0, i32 0, i32 0)
br i1 %cmp, label %taken, label %untaken
taken:
; CHECK-LABEL: taken:
; CHECK-NEXT: %obj = load
; CHECK-NEXT: gc.statepoint
; CHECK-NEXT: gc.relocate
; CHECK-NEXT: bitcast
; CHECK-NEXT: ret i64 addrspace(1)* %obj.relocated.casted
%obj = load i64 addrspace(1)*, i64 addrspace(1)** %loc
call i32 (void ()*, i32, i32, ...) @llvm.experimental.gc.statepoint.p0f_isVoidf(void ()* @foo, i32 0, i32 0, i32 0, i32 0)
ret i64 addrspace(1)* %obj
untaken:
ret i64 addrspace(1)* null
}
; A local kill should effect values live from a successor phi. Also, we
; should only propagate liveness from a phi to the appropriate predecessors.
define i64 addrspace(1)* @test3(i1 %cmp, i64 addrspace(1)** %loc) gc "statepoint-example" {
; CHECK-LABEL: @test3
entry:
br i1 %cmp, label %taken, label %untaken
taken:
; CHECK-LABEL: taken:
; CHECK-NEXT: gc.statepoint
; CHECK-NEXT: %obj = load
; CHECK-NEXT: gc.statepoint
; CHECK-NEXT: %obj.relocated = call coldcc i8 addrspace(1)*
; CHECK-NEXT: bitcast
; CHECK-NEXT: br label %merge
call i32 (void ()*, i32, i32, ...) @llvm.experimental.gc.statepoint.p0f_isVoidf(void ()* @foo, i32 0, i32 0, i32 0, i32 0)
%obj = load i64 addrspace(1)*, i64 addrspace(1)** %loc
call i32 (void ()*, i32, i32, ...) @llvm.experimental.gc.statepoint.p0f_isVoidf(void ()* @foo, i32 0, i32 0, i32 0, i32 0)
br label %merge
untaken:
; CHECK-LABEL: taken:
; CHECK-NEXT: gc.statepoint
; CHECK-NEXT: br label %merge
call i32 (void ()*, i32, i32, ...) @llvm.experimental.gc.statepoint.p0f_isVoidf(void ()* @foo, i32 0, i32 0, i32 0, i32 0)
br label %merge
merge:
%phi = phi i64 addrspace(1)* [ %obj, %taken ], [ null, %untaken ]
ret i64 addrspace(1)* %phi
}
; A base pointer must be live if it is needed at a later statepoint,
; even if the base pointer is otherwise unused.
define i64 addrspace(1)* @test4(i1 %cmp, i64 addrspace(1)* %obj) gc "statepoint-example" {
; CHECK-LABEL: @test4
entry:
; CHECK-LABEL: entry:
; CHECK-NEXT: %derived = getelementptr
; CHECK-NEXT: gc.statepoint
; CHECK-NEXT: %derived.relocated =
; CHECK-NEXT: bitcast
; CHECK-NEXT: %obj.relocated =
; CHECK-NEXT: bitcast
; CHECK-NEXT: gc.statepoint
; CHECK-NEXT: %derived.relocated1 =
; CHECK-NEXT: bitcast
; Note: It's legal to relocate obj again, but not strictly needed
; CHECK-NEXT: %obj.relocated2 =
; CHECK-NEXT: bitcast
; CHECK-NEXT: ret i64 addrspace(1)* %derived.relocated1.casted
;
%derived = getelementptr i64, i64 addrspace(1)* %obj, i64 8
call i32 (void ()*, i32, i32, ...) @llvm.experimental.gc.statepoint.p0f_isVoidf(void ()* @foo, i32 0, i32 0, i32 0, i32 0)
call i32 (void ()*, i32, i32, ...) @llvm.experimental.gc.statepoint.p0f_isVoidf(void ()* @foo, i32 0, i32 0, i32 0, i32 0)
ret i64 addrspace(1)* %derived
}
declare void @consume(...) readonly
; Make sure that a phi def visited during iteration is considered a kill.
; Also, liveness after base pointer analysis can change based on new uses,
; not just new defs.
define i64 addrspace(1)* @test5(i1 %cmp, i64 addrspace(1)* %obj) gc "statepoint-example" {
; CHECK-LABEL: @test5
entry:
br i1 %cmp, label %taken, label %untaken
taken:
; CHECK-LABEL: taken:
; CHECK-NEXT: gc.statepoint
; CHECK-NEXT: %obj.relocated = call coldcc i8 addrspace(1)*
; CHECK-NEXT: bitcast
; CHECK-NEXT: br label %merge
call i32 (void ()*, i32, i32, ...) @llvm.experimental.gc.statepoint.p0f_isVoidf(void ()* @foo, i32 0, i32 0, i32 0, i32 0)
br label %merge
untaken:
; CHECK-LABEL: untaken:
; CHECK-NEXT: br label %merge
br label %merge
merge:
; CHECK-LABEL: merge:
; CHECK-NEXT: %.0 = phi i64 addrspace(1)*
; CHECK-NEXT: %obj2a = phi
; CHECK-NEXT: @consume
; CHECK-NEXT: br label %final
%obj2a = phi i64 addrspace(1)* [ %obj, %taken ], [null, %untaken]
call void (...) @consume(i64 addrspace(1)* %obj2a)
br label %final
final:
; CHECK-LABEL: final:
; CHECK-NEXT: @consume
; CHECK-NEXT: ret i64 addrspace(1)* %.0
call void (...) @consume(i64 addrspace(1)* %obj2a)
ret i64 addrspace(1)* %obj
}
declare void @foo()
declare i32 @llvm.experimental.gc.statepoint.p0f_isVoidf(void ()*, i32, i32, ...)