mirror of
https://github.com/c64scene-ar/llvm-6502.git
synced 2024-11-04 22:07:27 +00:00
1bc7315c02
This is how it ignores the dead code:
1) When a dead branch target, say block B, is identified, all the
blocks dominated by B is dead as well.
2) The PHIs of those blocks in dominance-frontier(B) is updated such
that the operands corresponding to dead predecessors are replaced
by "UndefVal".
Using lattice's jargon, the "UndefVal" is the "Top" in essence.
Phi node like this "phi(v1 bb1, undef xx)" will be optimized into
"v1" if v1 is constant, or v1 is an instruction which dominate this
PHI node.
3) When analyzing the availability of a load L, all dead mem-ops which
L depends on disguise as a load which evaluate exactly same value as L.
4) The dead mem-ops will be materialized as "UndefVal" during code motion.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191017 91177308-0d34-0410-b5e6-96231b3b80d8
140 lines
7.3 KiB
LLVM
140 lines
7.3 KiB
LLVM
; RUN: opt -basicaa -gvn -S < %s | FileCheck %s
|
|
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-S128"
|
|
|
|
%"class.llvm::SmallVector" = type { %"class.llvm::SmallVectorImpl", [1 x %"union.llvm::SmallVectorBase::U"] }
|
|
%"class.llvm::SmallVectorImpl" = type { %"class.llvm::SmallVectorTemplateBase" }
|
|
%"class.llvm::SmallVectorTemplateBase" = type { %"class.llvm::SmallVectorTemplateCommon" }
|
|
%"class.llvm::SmallVectorTemplateCommon" = type { %"class.llvm::SmallVectorBase" }
|
|
%"class.llvm::SmallVectorBase" = type { i8*, i8*, i8*, %"union.llvm::SmallVectorBase::U" }
|
|
%"union.llvm::SmallVectorBase::U" = type { x86_fp80 }
|
|
|
|
; Function Attrs: ssp uwtable
|
|
define void @_Z4testv() #0 {
|
|
; CHECK: @_Z4testv()
|
|
; CHECK: invoke.cont:
|
|
; CHECK: br i1 true, label %new.notnull.i11, label %if.end.i14
|
|
; CHECK: Retry.i10:
|
|
|
|
entry:
|
|
%sv = alloca %"class.llvm::SmallVector", align 16
|
|
%0 = bitcast %"class.llvm::SmallVector"* %sv to i8*
|
|
call void @llvm.lifetime.start(i64 64, i8* %0) #1
|
|
%BeginX.i.i.i.i.i.i = getelementptr inbounds %"class.llvm::SmallVector"* %sv, i64 0, i32 0, i32 0, i32 0, i32 0, i32 0
|
|
%FirstEl.i.i.i.i.i.i = getelementptr inbounds %"class.llvm::SmallVector"* %sv, i64 0, i32 0, i32 0, i32 0, i32 0, i32 3
|
|
%1 = bitcast %"union.llvm::SmallVectorBase::U"* %FirstEl.i.i.i.i.i.i to i8*
|
|
store i8* %1, i8** %BeginX.i.i.i.i.i.i, align 16, !tbaa !0
|
|
%EndX.i.i.i.i.i.i = getelementptr inbounds %"class.llvm::SmallVector"* %sv, i64 0, i32 0, i32 0, i32 0, i32 0, i32 1
|
|
store i8* %1, i8** %EndX.i.i.i.i.i.i, align 8, !tbaa !0
|
|
%CapacityX.i.i.i.i.i.i = getelementptr inbounds %"class.llvm::SmallVector"* %sv, i64 0, i32 0, i32 0, i32 0, i32 0, i32 2
|
|
%add.ptr.i.i.i.i2.i.i = getelementptr inbounds %"union.llvm::SmallVectorBase::U"* %FirstEl.i.i.i.i.i.i, i64 2
|
|
%add.ptr.i.i.i.i.i.i = bitcast %"union.llvm::SmallVectorBase::U"* %add.ptr.i.i.i.i2.i.i to i8*
|
|
store i8* %add.ptr.i.i.i.i.i.i, i8** %CapacityX.i.i.i.i.i.i, align 16, !tbaa !0
|
|
%EndX.i = getelementptr inbounds %"class.llvm::SmallVector"* %sv, i64 0, i32 0, i32 0, i32 0, i32 0, i32 1
|
|
%2 = load i8** %EndX.i, align 8, !tbaa !0
|
|
%CapacityX.i = getelementptr inbounds %"class.llvm::SmallVector"* %sv, i64 0, i32 0, i32 0, i32 0, i32 0, i32 2
|
|
%cmp.i = icmp ult i8* %2, %add.ptr.i.i.i.i.i.i
|
|
br i1 %cmp.i, label %Retry.i, label %if.end.i
|
|
|
|
Retry.i: ; preds = %.noexc, %entry
|
|
%3 = phi i8* [ %2, %entry ], [ %.pre.i, %.noexc ]
|
|
%new.isnull.i = icmp eq i8* %3, null
|
|
br i1 %new.isnull.i, label %invoke.cont, label %new.notnull.i
|
|
|
|
new.notnull.i: ; preds = %Retry.i
|
|
%4 = bitcast i8* %3 to i32*
|
|
store i32 1, i32* %4, align 4, !tbaa !3
|
|
br label %invoke.cont
|
|
|
|
if.end.i: ; preds = %entry
|
|
%5 = getelementptr inbounds %"class.llvm::SmallVector"* %sv, i64 0, i32 0, i32 0, i32 0, i32 0
|
|
invoke void @_ZN4llvm15SmallVectorBase8grow_podEmm(%"class.llvm::SmallVectorBase"* %5, i64 0, i64 4)
|
|
to label %.noexc unwind label %lpad
|
|
|
|
.noexc: ; preds = %if.end.i
|
|
%.pre.i = load i8** %EndX.i, align 8, !tbaa !0
|
|
br label %Retry.i
|
|
|
|
invoke.cont: ; preds = %new.notnull.i, %Retry.i
|
|
%add.ptr.i = getelementptr inbounds i8* %3, i64 4
|
|
store i8* %add.ptr.i, i8** %EndX.i, align 8, !tbaa !0
|
|
%6 = load i8** %CapacityX.i, align 16, !tbaa !0
|
|
%cmp.i8 = icmp ult i8* %add.ptr.i, %6
|
|
br i1 %cmp.i8, label %new.notnull.i11, label %if.end.i14
|
|
|
|
Retry.i10: ; preds = %if.end.i14
|
|
%.pre.i13 = load i8** %EndX.i, align 8, !tbaa !0
|
|
%new.isnull.i9 = icmp eq i8* %.pre.i13, null
|
|
br i1 %new.isnull.i9, label %invoke.cont2, label %new.notnull.i11
|
|
|
|
new.notnull.i11: ; preds = %invoke.cont, %Retry.i10
|
|
%7 = phi i8* [ %.pre.i13, %Retry.i10 ], [ %add.ptr.i, %invoke.cont ]
|
|
%8 = bitcast i8* %7 to i32*
|
|
store i32 2, i32* %8, align 4, !tbaa !3
|
|
br label %invoke.cont2
|
|
|
|
if.end.i14: ; preds = %invoke.cont
|
|
%9 = getelementptr inbounds %"class.llvm::SmallVector"* %sv, i64 0, i32 0, i32 0, i32 0, i32 0
|
|
invoke void @_ZN4llvm15SmallVectorBase8grow_podEmm(%"class.llvm::SmallVectorBase"* %9, i64 0, i64 4)
|
|
to label %Retry.i10 unwind label %lpad
|
|
|
|
invoke.cont2: ; preds = %new.notnull.i11, %Retry.i10
|
|
%10 = phi i8* [ null, %Retry.i10 ], [ %7, %new.notnull.i11 ]
|
|
%add.ptr.i12 = getelementptr inbounds i8* %10, i64 4
|
|
store i8* %add.ptr.i12, i8** %EndX.i, align 8, !tbaa !0
|
|
invoke void @_Z1gRN4llvm11SmallVectorIiLj8EEE(%"class.llvm::SmallVector"* %sv)
|
|
to label %invoke.cont3 unwind label %lpad
|
|
|
|
invoke.cont3: ; preds = %invoke.cont2
|
|
%11 = load i8** %BeginX.i.i.i.i.i.i, align 16, !tbaa !0
|
|
%cmp.i.i.i.i19 = icmp eq i8* %11, %1
|
|
br i1 %cmp.i.i.i.i19, label %_ZN4llvm11SmallVectorIiLj8EED1Ev.exit21, label %if.then.i.i.i20
|
|
|
|
if.then.i.i.i20: ; preds = %invoke.cont3
|
|
call void @free(i8* %11) #1
|
|
br label %_ZN4llvm11SmallVectorIiLj8EED1Ev.exit21
|
|
|
|
_ZN4llvm11SmallVectorIiLj8EED1Ev.exit21: ; preds = %invoke.cont3, %if.then.i.i.i20
|
|
call void @llvm.lifetime.end(i64 64, i8* %0) #1
|
|
ret void
|
|
|
|
lpad: ; preds = %if.end.i14, %if.end.i, %invoke.cont2
|
|
%12 = landingpad { i8*, i32 } personality i8* bitcast (i32 (...)* @__gxx_personality_v0 to i8*)
|
|
cleanup
|
|
%13 = load i8** %BeginX.i.i.i.i.i.i, align 16, !tbaa !0
|
|
%cmp.i.i.i.i = icmp eq i8* %13, %1
|
|
br i1 %cmp.i.i.i.i, label %eh.resume, label %if.then.i.i.i
|
|
|
|
if.then.i.i.i: ; preds = %lpad
|
|
call void @free(i8* %13) #1
|
|
br label %eh.resume
|
|
|
|
eh.resume: ; preds = %if.then.i.i.i, %lpad
|
|
resume { i8*, i32 } %12
|
|
}
|
|
|
|
; Function Attrs: nounwind
|
|
declare void @llvm.lifetime.start(i64, i8* nocapture) #1
|
|
|
|
declare i32 @__gxx_personality_v0(...)
|
|
|
|
declare void @_Z1gRN4llvm11SmallVectorIiLj8EEE(%"class.llvm::SmallVector"*) #2
|
|
|
|
; Function Attrs: nounwind
|
|
declare void @llvm.lifetime.end(i64, i8* nocapture) #1
|
|
|
|
declare void @_ZN4llvm15SmallVectorBase8grow_podEmm(%"class.llvm::SmallVectorBase"*, i64, i64) #2
|
|
|
|
; Function Attrs: nounwind
|
|
declare void @free(i8* nocapture) #3
|
|
|
|
attributes #0 = { ssp uwtable "less-precise-fpmad"="false" "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "stack-protector-buffer-size"="8" "unsafe-fp-math"="false" "use-soft-float"="false" }
|
|
attributes #1 = { nounwind }
|
|
attributes #2 = { "less-precise-fpmad"="false" "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "stack-protector-buffer-size"="8" "unsafe-fp-math"="false" "use-soft-float"="false" }
|
|
attributes #3 = { nounwind "less-precise-fpmad"="false" "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "stack-protector-buffer-size"="8" "unsafe-fp-math"="false" "use-soft-float"="false" }
|
|
|
|
!0 = metadata !{metadata !"any pointer", metadata !1}
|
|
!1 = metadata !{metadata !"omnipotent char", metadata !2}
|
|
!2 = metadata !{metadata !"Simple C/C++ TBAA"}
|
|
!3 = metadata !{metadata !"int", metadata !1}
|
|
|