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|
; RUN: opt -S -gvn-hoist < %s | FileCheck %s
; Checking gvn-hoist in case of indirect branches.
; Check that the bitcast is is not hoisted because it is after an indirect call
; CHECK-LABEL: @foo
; CHECK-LABEL: l1.preheader:
; CHECK-NEXT: bitcast
; CHECK-LABEL: l1
; CHECK: bitcast
%class.bar = type { i8*, %class.base* }
%class.base = type { i32 (...)** }
@bar = local_unnamed_addr global i32 ()* null, align 8
@bar1 = local_unnamed_addr global i32 ()* null, align 8
define i32 @foo(i32* nocapture readonly %i) {
entry:
%agg.tmp = alloca %class.bar, align 8
%x= getelementptr inbounds %class.bar, %class.bar* %agg.tmp, i64 0, i32 1
%y = load %class.base*, %class.base** %x, align 8
%0 = load i32, i32* %i, align 4
%.off = add i32 %0, -1
%switch = icmp ult i32 %.off, 2
br i1 %switch, label %l1.preheader, label %sw.default
l1.preheader: ; preds = %sw.default, %entry
%b1 = bitcast %class.base* %y to void (%class.base*)***
br label %l1
l1: ; preds = %l1.preheader, %l1
%1 = load i32 ()*, i32 ()** @bar, align 8
%call = tail call i32 %1()
%b2 = bitcast %class.base* %y to void (%class.base*)***
br label %l1
sw.default: ; preds = %entry
%2 = load i32 ()*, i32 ()** @bar1, align 8
%call2 = tail call i32 %2()
br label %l1.preheader
}
; Any instruction inside an infinite loop will not be hoisted because
; there is no path to exit of the function.
; CHECK-LABEL: @foo1
; CHECK-LABEL: l1.preheader:
; CHECK-NEXT: bitcast
; CHECK-LABEL: l1:
; CHECK: bitcast
define i32 @foo1(i32* nocapture readonly %i) {
entry:
%agg.tmp = alloca %class.bar, align 8
%x= getelementptr inbounds %class.bar, %class.bar* %agg.tmp, i64 0, i32 1
%y = load %class.base*, %class.base** %x, align 8
%0 = load i32, i32* %i, align 4
%.off = add i32 %0, -1
%switch = icmp ult i32 %.off, 2
br i1 %switch, label %l1.preheader, label %sw.default
l1.preheader: ; preds = %sw.default, %entry
%b1 = bitcast %class.base* %y to void (%class.base*)***
%y1 = load %class.base*, %class.base** %x, align 8
br label %l1
l1: ; preds = %l1.preheader, %l1
%b2 = bitcast %class.base* %y to void (%class.base*)***
%1 = load i32 ()*, i32 ()** @bar, align 8
%y2 = load %class.base*, %class.base** %x, align 8
%call = tail call i32 %1()
br label %l1
sw.default: ; preds = %entry
%2 = load i32 ()*, i32 ()** @bar1, align 8
%call2 = tail call i32 %2()
br label %l1.preheader
}
; Check that bitcast is hoisted even when one of them is partially redundant.
; CHECK-LABEL: @test13
; CHECK: bitcast
; CHECK-NOT: bitcast
define i32 @test13(i32* %P, i8* %Ptr, i32* nocapture readonly %i) {
entry:
%agg.tmp = alloca %class.bar, align 8
%x= getelementptr inbounds %class.bar, %class.bar* %agg.tmp, i64 0, i32 1
%y = load %class.base*, %class.base** %x, align 8
indirectbr i8* %Ptr, [label %BrBlock, label %B2]
B2:
%b1 = bitcast %class.base* %y to void (%class.base*)***
store i32 4, i32 *%P
br label %BrBlock
BrBlock:
%b2 = bitcast %class.base* %y to void (%class.base*)***
%L = load i32, i32* %P
%C = icmp eq i32 %L, 42
br i1 %C, label %T, label %F
T:
ret i32 123
F:
ret i32 1422
}
; Check that the bitcast is not hoisted because anticipability
; cannot be guaranteed here as one of the indirect branch targets
; do not have the bitcast instruction.
; CHECK-LABEL: @test14
; CHECK-LABEL: B2:
; CHECK-NEXT: bitcast
; CHECK-LABEL: BrBlock:
; CHECK-NEXT: bitcast
define i32 @test14(i32* %P, i8* %Ptr, i32* nocapture readonly %i) {
entry:
%agg.tmp = alloca %class.bar, align 8
%x= getelementptr inbounds %class.bar, %class.bar* %agg.tmp, i64 0, i32 1
%y = load %class.base*, %class.base** %x, align 8
indirectbr i8* %Ptr, [label %BrBlock, label %B2, label %T]
B2:
%b1 = bitcast %class.base* %y to void (%class.base*)***
store i32 4, i32 *%P
br label %BrBlock
BrBlock:
%b2 = bitcast %class.base* %y to void (%class.base*)***
%L = load i32, i32* %P
%C = icmp eq i32 %L, 42
br i1 %C, label %T, label %F
T:
%pi = load i32, i32* %i, align 4
ret i32 %pi
F:
%pl = load i32, i32* %P
ret i32 %pl
}
; Check that the bitcast is not hoisted because of a cycle
; due to indirect branches
; CHECK-LABEL: @test16
; CHECK-LABEL: B2:
; CHECK-NEXT: bitcast
; CHECK-LABEL: BrBlock:
; CHECK-NEXT: bitcast
define i32 @test16(i32* %P, i8* %Ptr, i32* nocapture readonly %i) {
entry:
%agg.tmp = alloca %class.bar, align 8
%x= getelementptr inbounds %class.bar, %class.bar* %agg.tmp, i64 0, i32 1
%y = load %class.base*, %class.base** %x, align 8
indirectbr i8* %Ptr, [label %BrBlock, label %B2]
B2:
%b1 = bitcast %class.base* %y to void (%class.base*)***
%0 = load i32, i32* %i, align 4
store i32 %0, i32 *%P
br label %BrBlock
BrBlock:
%b2 = bitcast %class.base* %y to void (%class.base*)***
%L = load i32, i32* %P
%C = icmp eq i32 %L, 42
br i1 %C, label %T, label %F
T:
indirectbr i32* %P, [label %BrBlock, label %B2]
F:
indirectbr i8* %Ptr, [label %BrBlock, label %B2]
}
@_ZTIi = external constant i8*
; Check that an instruction is not hoisted out of landing pad (%lpad4)
; Also within a landing pad no redundancies are removed by gvn-hoist,
; however an instruction may be hoisted into a landing pad if
; landing pad has direct branches (e.g., %lpad to %catch1, %catch)
; This CFG has a cycle (%lpad -> %catch1 -> %lpad4 -> %lpad)
; CHECK-LABEL: @foo2
; Check that nothing gets hoisted out of %lpad
; CHECK-LABEL: lpad:
; CHECK: %bc1 = add i32 %0, 10
; CHECK: %bc7 = add i32 %0, 10
; Check that the add is hoisted
; CHECK-LABEL: catch1:
; CHECK-NEXT: invoke
; Check that the add is hoisted
; CHECK-LABEL: catch:
; CHECK-NEXT: load
; Check that other adds are not hoisted
; CHECK-LABEL: lpad4:
; CHECK: %bc5 = add i32 %0, 10
; CHECK-LABEL: unreachable:
; CHECK: %bc2 = add i32 %0, 10
; Function Attrs: noinline uwtable
define i32 @foo2(i32* nocapture readonly %i) local_unnamed_addr personality i8* bitcast (i32 (...)* @__gxx_personality_v0 to i8*) {
entry:
%0 = load i32, i32* %i, align 4
%cmp = icmp eq i32 %0, 0
br i1 %cmp, label %try.cont, label %if.then
if.then:
%exception = tail call i8* @__cxa_allocate_exception(i64 4) #2
%1 = bitcast i8* %exception to i32*
store i32 %0, i32* %1, align 16
invoke void @__cxa_throw(i8* %exception, i8* bitcast (i8** @_ZTIi to i8*), i8* null) #3
to label %unreachable unwind label %lpad
lpad:
%2 = landingpad { i8*, i32 }
catch i8* bitcast (i8** @_ZTIi to i8*)
catch i8* null
%bc1 = add i32 %0, 10
%3 = extractvalue { i8*, i32 } %2, 0
%4 = extractvalue { i8*, i32 } %2, 1
%5 = tail call i32 @llvm.eh.typeid.for(i8* bitcast (i8** @_ZTIi to i8*)) #2
%matches = icmp eq i32 %4, %5
%bc7 = add i32 %0, 10
%6 = tail call i8* @__cxa_begin_catch(i8* %3) #2
br i1 %matches, label %catch1, label %catch
catch1:
%bc3 = add i32 %0, 10
invoke void @__cxa_rethrow() #3
to label %unreachable unwind label %lpad4
catch:
%bc4 = add i32 %0, 10
%7 = load i32, i32* %i, align 4
%add = add nsw i32 %7, 1
tail call void @__cxa_end_catch()
br label %try.cont
lpad4:
%8 = landingpad { i8*, i32 }
cleanup
%bc5 = add i32 %0, 10
tail call void @__cxa_end_catch() #2
invoke void @__cxa_throw(i8* %exception, i8* bitcast (i8** @_ZTIi to i8*), i8* null) #3
to label %unreachable unwind label %lpad
try.cont:
%k.0 = phi i32 [ %add, %catch ], [ 0, %entry ]
%bc6 = add i32 %0, 10
ret i32 %k.0
unreachable:
%bc2 = add i32 %0, 10
ret i32 %bc2
}
declare i8* @__cxa_allocate_exception(i64) local_unnamed_addr
declare void @__cxa_throw(i8*, i8*, i8*) local_unnamed_addr
declare i32 @__gxx_personality_v0(...)
; Function Attrs: nounwind readnone
declare i32 @llvm.eh.typeid.for(i8*) #1
declare i8* @__cxa_begin_catch(i8*) local_unnamed_addr
declare void @__cxa_end_catch() local_unnamed_addr
declare void @__cxa_rethrow() local_unnamed_addr
attributes #1 = { nounwind readnone }
attributes #2 = { nounwind }
attributes #3 = { noreturn }
|
