Revert "TRE: make TRE a bit more aggressive"

This reverts commit r219899.

This also updates byval-tail-call.ll to make it clear what was breaking.
Adding r219899 again will cause the load/store to disappear.

llvm-svn: 220093
This commit is contained in:
Rafael Espindola 2014-10-17 21:25:48 +00:00
parent ba637db298
commit 7da1ea83a9
4 changed files with 14 additions and 40 deletions

View File

@ -249,7 +249,12 @@ bool TailCallElim::markTails(Function &F, bool &AllCallsAreTailCalls) {
return false;
AllCallsAreTailCalls = true;
// The local stack holds all alloca instructions and all byval arguments.
AllocaDerivedValueTracker Tracker;
for (Argument &Arg : F.args()) {
if (Arg.hasByValAttr())
Tracker.walk(&Arg);
}
for (auto &BB : F) {
for (auto &I : BB)
if (AllocaInst *AI = dyn_cast<AllocaInst>(&I))
@ -305,8 +310,9 @@ bool TailCallElim::markTails(Function &F, bool &AllCallsAreTailCalls) {
for (auto &Arg : CI->arg_operands()) {
if (isa<Constant>(Arg.getUser()))
continue;
if (isa<Argument>(Arg.getUser()))
continue;
if (Argument *A = dyn_cast<Argument>(Arg.getUser()))
if (!A->hasByValAttr())
continue;
SafeToTail = false;
break;
}

View File

@ -1,4 +1,4 @@
; RUN: opt < %s -tailcallelim -inline -instcombine -dse -S | FileCheck %s
; RUN: opt < %s -basicaa -tailcallelim -inline -instcombine -dse -S | FileCheck %s
; PR7272
; Calls that capture byval parameters cannot be marked as tail calls. Other
@ -30,8 +30,10 @@ define internal void @qux(i32* byval %x) {
define void @frob(i32* %x) {
; CHECK-LABEL: define void @frob(
; CHECK: alloca i32
; CHECK: {{^ *}}tail call void @ext(
; CHECK: %[[POS:.*]] = alloca i32
; CHECK: %[[VAL:.*]] = load i32* %x
; CHECK: store i32 %[[VAL]], i32* %[[POS]]
; CHECK: {{^ *}}call void @ext(i32* %[[POS]]
; CHECK: tail call void @ext(i32* null)
; CHECK: ret void
tail call void @qux(i32* byval %x)

View File

@ -147,7 +147,7 @@ cond_false:
; Don't tail call if a byval arg is captured.
define void @test9(i32* byval %a) {
; CHECK-LABEL: define void @test9(
; CHECK: {{^ *}}tail call void @use(
; CHECK: {{^ *}}call void @use(
call void @use(i32* %a)
ret void
}

View File

@ -1,34 +0,0 @@
; RUN: opt -mtriple i386 -Os -S %s -o - | FileCheck %s
; RUN: opt -mtriple x86_64 -Os -S %s -o - | FileCheck %s
; RUN: opt -mtriple armv7 -Os -S %s -o - | FileCheck %s
%struct.D16 = type { [16 x double] }
declare void @_Z2OpP3D16PKS_S2_(%struct.D16*, %struct.D16*, %struct.D16*)
define void @_Z7TestRefRK3D16S1_(%struct.D16* noalias sret %agg.result, %struct.D16* %RHS, %struct.D16* %LHS) {
%1 = alloca %struct.D16*, align 8
%2 = alloca %struct.D16*, align 8
store %struct.D16* %RHS, %struct.D16** %1, align 8
store %struct.D16* %LHS, %struct.D16** %2, align 8
%3 = load %struct.D16** %1, align 8
%4 = load %struct.D16** %2, align 8
call void @_Z2OpP3D16PKS_S2_(%struct.D16* %agg.result, %struct.D16* %3, %struct.D16* %4)
ret void
}
; CHECK: define void @_Z7TestRefRK3D16S1_({{.*}}) {
; CHECK: tail call void @_Z2OpP3D16PKS_S2_(%struct.D16* %agg.result, %struct.D16* %RHS, %struct.D16* %LHS)
; CHECK: ret void
; CHECK: }
define void @_Z7TestVal3D16S_(%struct.D16* noalias sret %agg.result, %struct.D16* byval align 8 %RHS, %struct.D16* byval align 8 %LHS) {
call void @_Z2OpP3D16PKS_S2_(%struct.D16* %agg.result, %struct.D16* %RHS, %struct.D16* %LHS)
ret void
}
; CHECK: define void @_Z7TestVal3D16S_({{.*}}) {
; CHECK: tail call void @_Z2OpP3D16PKS_S2_(%struct.D16* %agg.result, %struct.D16* %RHS, %struct.D16* %LHS)
; CHECK: ret void
; CHECK: }