llvm/test/Transforms/SimplifyCFG/speculate-with-offset.ll
Dan Gohman 4d70a29490 Factor out Instruction::isSafeToSpeculativelyExecute's code for
testing for dereferenceable pointers into a helper function,
isDereferenceablePointer.  Teach it how to reason about GEPs
with simple non-zero indices.

Also eliminate ArgumentPromtion's IsAlwaysValidPointer,
which didn't check for weak externals or out of range gep
indices.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@118840 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-11 21:23:25 +00:00

95 lines
2.6 KiB
LLVM

; RUN: opt -simplifycfg -S < %s | FileCheck %s
; This load is safe to speculate, as it's from a safe offset
; within an alloca.
; CHECK: @yes
; CHECK-NOT: br
define void @yes(i1 %c) nounwind {
entry:
%a = alloca [4 x i64*], align 8
%__a.addr = getelementptr [4 x i64*]* %a, i64 0, i64 3
call void @frob(i64** %__a.addr)
br i1 %c, label %if.then, label %if.end
if.then: ; preds = %entry
br label %return
if.end: ; preds = %entry
%tmp5 = load i64** %__a.addr, align 8
br label %return
return: ; preds = %if.end, %if.then
%storemerge = phi i64* [ undef, %if.then ], [ %tmp5, %if.end ]
ret void
}
; CHECK: @no0
; CHECK: br i1 %c
define void @no0(i1 %c) nounwind {
entry:
%a = alloca [4 x i64*], align 8
%__a.addr = getelementptr [4 x i64*]* %a, i64 0, i64 4
call void @frob(i64** %__a.addr)
br i1 %c, label %if.then, label %if.end
if.then: ; preds = %entry
br label %return
if.end: ; preds = %entry
%tmp5 = load i64** %__a.addr, align 8
br label %return
return: ; preds = %if.end, %if.then
%storemerge = phi i64* [ undef, %if.then ], [ %tmp5, %if.end ]
ret void
}
; CHECK: @no1
; CHECK: br i1 %c
define void @no1(i1 %c, i64 %n) nounwind {
entry:
%a = alloca [4 x i64*], align 8
%__a.addr = getelementptr [4 x i64*]* %a, i64 0, i64 %n
call void @frob(i64** %__a.addr)
br i1 %c, label %if.then, label %if.end
if.then: ; preds = %entry
br label %return
if.end: ; preds = %entry
%tmp5 = load i64** %__a.addr, align 8
br label %return
return: ; preds = %if.end, %if.then
%storemerge = phi i64* [ undef, %if.then ], [ %tmp5, %if.end ]
ret void
}
; CHECK: @no2
; CHECK: br i1 %c
define void @no2(i1 %c, i64 %n) nounwind {
entry:
%a = alloca [4 x i64*], align 8
%__a.addr = getelementptr [4 x i64*]* %a, i64 1, i64 0
call void @frob(i64** %__a.addr)
br i1 %c, label %if.then, label %if.end
if.then: ; preds = %entry
br label %return
if.end: ; preds = %entry
%tmp5 = load i64** %__a.addr, align 8
br label %return
return: ; preds = %if.end, %if.then
%storemerge = phi i64* [ undef, %if.then ], [ %tmp5, %if.end ]
ret void
}
declare void @frob(i64** nocapture %p)