fast-isel-deadcode.ll
5.66 KB
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; RUN: llc < %s | FileCheck %s
;
; Generated with clang -O2 -S -emit-llvm
;
; /* Test 1 */
; extern "C" bool bar (long double);
; __attribute__((optnone))
; extern "C" bool foo(long double x, long double y)
; {
; return (x == y) || (bar(x));
; }
;
; /* Test 2 */
; struct FVector {
; float x, y, z;
; inline __attribute__((always_inline)) FVector(float f): x(f), y(f), z(f) {}
; inline __attribute__((always_inline)) FVector func(float p) const
; {
; if( x == 1.f ) {
; return *this;
; } else if( x < p ) {
; return FVector(0.f);
; }
; return FVector(x);
; }
; };
;
; __attribute__((optnone))
; int main()
; {
; FVector v(1.0);
; v = v.func(1.e-8);
; return 0;
; }
;
; ModuleID = 'test.cpp'
target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-unknown-linux-gnu"
%struct.FVector = type { float, float, float }
define zeroext i1 @foo(x86_fp80 %x, x86_fp80 %y) noinline optnone {
entry:
%x.addr = alloca x86_fp80, align 16
%y.addr = alloca x86_fp80, align 16
store x86_fp80 %x, x86_fp80* %x.addr, align 16
store x86_fp80 %y, x86_fp80* %y.addr, align 16
%0 = load x86_fp80, x86_fp80* %x.addr, align 16
%1 = load x86_fp80, x86_fp80* %y.addr, align 16
%cmp = fcmp oeq x86_fp80 %0, %1
; Test 1
; Make sure that there is no dead code generated
; from Fast-ISel Phi-node handling. We should only
; see one movb of the constant 1, feeding the PHI
; node in lor.end. This covers the code path with
; handlePHINodesInSuccessorBlocks() returning true.
;
; CHECK-LABEL: foo:
; CHECK: movb $1,
; CHECK-NOT: movb $1,
; CHECK-LABEL: .LBB0_1:
br i1 %cmp, label %lor.end, label %lor.rhs
lor.rhs: ; preds = %entry
%2 = load x86_fp80, x86_fp80* %x.addr, align 16
%call = call zeroext i1 @bar(x86_fp80 %2)
br label %lor.end
lor.end: ; preds = %lor.rhs, %entry
%3 = phi i1 [ true, %entry ], [ %call, %lor.rhs ]
ret i1 %3
}
declare zeroext i1 @bar(x86_fp80)
define i32 @main() noinline optnone {
entry:
%retval = alloca i32, align 4
%v = alloca %struct.FVector, align 4
%ref.tmp = alloca %struct.FVector, align 4
%tmp = alloca { <2 x float>, float }, align 8
store i32 0, i32* %retval, align 4
%0 = bitcast %struct.FVector* %v to i8*
call void @llvm.lifetime.start.p0i8(i64 12, i8* %0) nounwind
%x.i = getelementptr inbounds %struct.FVector, %struct.FVector* %v, i64 0, i32 0
store float 1.000000e+00, float* %x.i, align 4
%y.i = getelementptr inbounds %struct.FVector, %struct.FVector* %v, i64 0, i32 1
store float 1.000000e+00, float* %y.i, align 4
%z.i = getelementptr inbounds %struct.FVector, %struct.FVector* %v, i64 0, i32 2
store float 1.000000e+00, float* %z.i, align 4
%x.i.1 = getelementptr inbounds %struct.FVector, %struct.FVector* %v, i64 0, i32 0
%1 = load float, float* %x.i.1, align 4
%cmp.i = fcmp oeq float %1, 1.000000e+00
br i1 %cmp.i, label %if.then.i, label %if.else.i
if.then.i: ; preds = %entry
%retval.sroa.0.0..sroa_cast.i = bitcast %struct.FVector* %v to <2 x float>*
%retval.sroa.0.0.copyload.i = load <2 x float>, <2 x float>* %retval.sroa.0.0..sroa_cast.i, align 4
%retval.sroa.6.0..sroa_idx16.i = getelementptr inbounds %struct.FVector, %struct.FVector* %v, i64 0, i32 2
%retval.sroa.6.0.copyload.i = load float, float* %retval.sroa.6.0..sroa_idx16.i, align 4
br label %func.exit
if.else.i: ; preds = %entry
; Test 2
; In order to feed the first PHI node in func.exit handlePHINodesInSuccessorBlocks()
; generates a local value instruction, but it cannot handle the second PHI node and
; returns false to let SelectionDAGISel handle both cases. Make sure the generated
; local value instruction is removed.
; CHECK-LABEL: main:
; CHECK-LABEL: .LBB1_2:
; CHECK: xorps [[REG:%xmm[0-7]]], [[REG]]
; CHECK-NOT: xorps [[REG]], [[REG]]
; CHECK-LABEL: .LBB1_3:
%cmp3.i = fcmp olt float %1, 0x3E45798EE0000000
br i1 %cmp3.i, label %func.exit, label %if.end.5.i
if.end.5.i: ; preds = %if.else.i
%retval.sroa.0.0.vec.insert13.i = insertelement <2 x float> undef, float %1, i32 0
%retval.sroa.0.4.vec.insert15.i = insertelement <2 x float> %retval.sroa.0.0.vec.insert13.i, float %1, i32 1
br label %func.exit
func.exit: ; preds = %if.then.i, %if.else.i, %if.end.5.i
%retval.sroa.6.0.i = phi float [ %retval.sroa.6.0.copyload.i, %if.then.i ], [ %1, %if.end.5.i ], [ 0.000000e+00, %if.else.i ]
%retval.sroa.0.0.i = phi <2 x float> [ %retval.sroa.0.0.copyload.i, %if.then.i ], [ %retval.sroa.0.4.vec.insert15.i, %if.end.5.i ], [ zeroinitializer, %if.else.i ]
%.fca.0.insert.i = insertvalue { <2 x float>, float } undef, <2 x float> %retval.sroa.0.0.i, 0
%.fca.1.insert.i = insertvalue { <2 x float>, float } %.fca.0.insert.i, float %retval.sroa.6.0.i, 1
store { <2 x float>, float } %.fca.1.insert.i, { <2 x float>, float }* %tmp, align 8
%2 = bitcast { <2 x float>, float }* %tmp to i8*
%3 = bitcast %struct.FVector* %ref.tmp to i8*
call void @llvm.memcpy.p0i8.p0i8.i64(i8* align 4 %3, i8* align 4 %2, i64 12, i1 false)
%4 = bitcast %struct.FVector* %v to i8*
%5 = bitcast %struct.FVector* %ref.tmp to i8*
call void @llvm.memcpy.p0i8.p0i8.i64(i8* align 4 %4, i8* align 4 %5, i64 12, i1 false)
%6 = bitcast %struct.FVector* %v to i8*
call void @llvm.lifetime.end.p0i8(i64 12, i8* %6) nounwind
ret i32 0
}
declare void @llvm.lifetime.start.p0i8(i64, i8* nocapture) argmemonly nounwind
declare void @llvm.memcpy.p0i8.p0i8.i64(i8* nocapture, i8* nocapture readonly, i64, i1) argmemonly nounwind
declare void @llvm.lifetime.end.p0i8(i64, i8* nocapture) argmemonly nounwind