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; RUN: opt < %s -basicaa -licm -S | FileCheck %s
; RUN: opt -aa-pipeline=basic-aa -passes='require<aa>,require<targetir>,require<scalar-evolution>,require<opt-remark-emit>,loop(licm)' -S %s | FileCheck %s
target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-unknown-linux-gnu"
; Make sure we don't hoist the store out of the loop; %a would
; have the wrong value if f() unwinds
define void @test1(i32* nocapture noalias %a, i1 zeroext %y) uwtable {
entry:
br label %for.body
for.body:
%i.03 = phi i32 [ 0, %entry ], [ %inc, %for.inc ]
%0 = load i32, i32* %a, align 4
%add = add nsw i32 %0, 1
store i32 %add, i32* %a, align 4
br i1 %y, label %if.then, label %for.inc
; CHECK: define void @test1
; CHECK: load i32, i32*
; CHECK-NEXT: add
; CHECK-NEXT: store i32
if.then:
tail call void @f()
br label %for.inc
for.inc:
%inc = add nuw nsw i32 %i.03, 1
%exitcond = icmp eq i32 %inc, 10000
br i1 %exitcond, label %for.cond.cleanup, label %for.body
for.cond.cleanup:
ret void
}
; We can hoist the store out of the loop here; if f() unwinds,
; the lifetime of %a ends.
define void @test2(i1 zeroext %y) uwtable {
entry:
%a = alloca i32
br label %for.body
for.body:
%i.03 = phi i32 [ 0, %entry ], [ %inc, %for.inc ]
%0 = load i32, i32* %a, align 4
%add = add nsw i32 %0, 1
store i32 %add, i32* %a, align 4
br i1 %y, label %if.then, label %for.inc
if.then:
tail call void @f()
br label %for.inc
for.inc:
%inc = add nuw nsw i32 %i.03, 1
%exitcond = icmp eq i32 %inc, 10000
br i1 %exitcond, label %for.cond.cleanup, label %for.body
for.cond.cleanup:
; CHECK: define void @test2
; CHECK: store i32
; CHECK-NEXT: ret void
ret void
}
@_ZTIi = external constant i8*
; In this test, the loop is within a try block. There is an explicit unwind edge out of the loop.
; Make sure this edge is treated as a loop exit, and that the loads and stores are promoted as
; expected
define void @loop_within_tryblock() personality i8* bitcast (i32 (...)* @__gxx_personality_v0 to i8*) {
entry:
%a = alloca i32, align 4
store i32 0, i32* %a, align 4
br label %for.cond
for.cond:
%i.0 = phi i32 [ 0, %entry ], [ %inc, %for.inc ]
%cmp = icmp slt i32 %i.0, 1024
br i1 %cmp, label %for.body, label %for.end
; CHECK: for.body:
; CHECK-NOT: load
; CHECK-NOT: store
; CHECK: invoke
for.body:
%0 = load i32, i32* %a, align 4
%add = add nsw i32 %0, 1
store i32 %add, i32* %a, align 4
invoke void @boo()
to label %invoke.cont unwind label %lpad
invoke.cont:
br label %for.inc
for.inc:
%inc = add nsw i32 %i.0, 1
br label %for.cond
; CHECK: lpad:
; CHECK: store
; CHECK: br
lpad:
%1 = landingpad { i8*, i32 }
catch i8* bitcast (i8** @_ZTIi to i8*)
%2 = extractvalue { i8*, i32 } %1, 0
%3 = extractvalue { i8*, i32 } %1, 1
br label %catch.dispatch
catch.dispatch:
%4 = call i32 @llvm.eh.typeid.for(i8* bitcast (i8** @_ZTIi to i8*)) #3
%matches = icmp eq i32 %3, %4
br i1 %matches, label %catch, label %eh.resume
catch:
%5 = call i8* @__cxa_begin_catch(i8* %2) #3
%6 = bitcast i8* %5 to i32*
%7 = load i32, i32* %6, align 4
call void @__cxa_end_catch() #3
br label %try.cont
try.cont:
ret void
for.end:
br label %try.cont
eh.resume:
%lpad.val = insertvalue { i8*, i32 } undef, i8* %2, 0
%lpad.val3 = insertvalue { i8*, i32 } %lpad.val, i32 %3, 1
resume { i8*, i32 } %lpad.val3
}
; The malloc'ed memory is not capture and therefore promoted.
define void @malloc_no_capture() #0 personality i8* bitcast (i32 (...)* @__gxx_personality_v0 to i8*) {
entry:
%call = call i8* @malloc(i64 4)
%0 = bitcast i8* %call to i32*
br label %for.body
; CHECK: for.body:
; CHECK-NOT: load
; CHECK-NOT: store
; CHECK: br
for.body:
%i.0 = phi i32 [ 0, %entry ], [ %inc, %for.latch ]
%1 = load i32, i32* %0, align 4
%add = add nsw i32 %1, 1
store i32 %add, i32* %0, align 4
br label %for.call
for.call:
invoke void @boo()
to label %invoke.cont unwind label %lpad
invoke.cont:
br label %for.latch
for.latch:
%inc = add i32 %i.0, 1
%cmp = icmp slt i32 %i.0, 1024
br i1 %cmp, label %for.body, label %for.end
for.end:
br label %fun.ret
lpad:
%2 = landingpad { i8*, i32 }
catch i8* null
%3 = extractvalue { i8*, i32 } %2, 0
%4 = extractvalue { i8*, i32 } %2, 1
br label %catch
catch:
%5 = call i8* @__cxa_begin_catch(i8* %3) #4
%6 = bitcast i32* %0 to i8*
call void @free(i8* %6)
call void @__cxa_end_catch()
br label %fun.ret
fun.ret:
ret void
}
; The malloc'ed memory can be captured and therefore not promoted.
define void @malloc_capture(i32** noalias %A) personality i8* bitcast (i32 (...)* @__gxx_personality_v0 to i8*) {
entry:
%call = call i8* @malloc(i64 4)
%0 = bitcast i8* %call to i32*
br label %for.body
; CHECK: for.body:
; CHECK: load
; CHECK: store
; CHECK: br
for.body:
%i.0 = phi i32 [ 0, %entry ], [ %inc, %for.latch ]
%1 = load i32, i32* %0, align 4
%add = add nsw i32 %1, 1
store i32 %add, i32* %0, align 4
br label %for.call
for.call:
invoke void @boo_readnone()
to label %invoke.cont unwind label %lpad
invoke.cont:
br label %for.latch
for.latch:
store i32* %0, i32** %A
%inc = add i32 %i.0, 1
%cmp = icmp slt i32 %i.0, 1024
br i1 %cmp, label %for.body, label %for.end
for.end:
br label %fun.ret
lpad:
%2 = landingpad { i8*, i32 }
catch i8* null
%3 = extractvalue { i8*, i32 } %2, 0
%4 = extractvalue { i8*, i32 } %2, 1
br label %catch
catch:
%5 = call i8* @__cxa_begin_catch(i8* %3) #4
%6 = bitcast i32* %0 to i8*
call void @free(i8* %6)
call void @__cxa_end_catch()
br label %fun.ret
fun.ret:
ret void
}
; Function Attrs: nounwind
declare noalias i8* @malloc(i64)
; Function Attrs: nounwind
declare void @free(i8* nocapture)
declare void @boo()
; This is an artifical example, readnone functions by definition cannot unwind
; exceptions by calling the C++ exception throwing methods
; This function should only be used to test malloc_capture.
declare void @boo_readnone() readnone
declare i32 @__gxx_personality_v0(...)
declare i8* @__cxa_begin_catch(i8*)
declare void @__cxa_end_catch()
declare i32 @llvm.eh.typeid.for(i8*)
declare void @f() uwtable
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