target datalayout = "e-m:e-i64:64-n32:64" target triple = "powerpc64le-unknown-linux-gnu" ; This file mainly tests that one of the ISEL instruction in the group uses the same register for operand RT, RA, RB ; This redudant ISEL is introduced during simple register coalescing stage. ; Simple register coalescing first create the foldable ISEL instruction as we have seen in expand-foldable-isel.ll: ; %vreg85<def> = ISEL8 %vreg83, %vreg83, %vreg33:sub_eq ; Later the register coalescer figures out it could further coalesce %vreg85 with %vreg83: ; merge %vreg85:1@2288r into %vreg83:5@400B --> @400B ; erased: 2288r %vreg85<def> = COPY %vreg83 ; After that we have: ; updated: 1504B %vreg83<def> = ISEL8 %vreg83, %vreg83, %vreg33:sub_eq ; RUN: llc -verify-machineinstrs -O2 -ppc-asm-full-reg-names -mcpu=pwr7 -ppc-gen-isel=true < %s | FileCheck %s --check-prefix=CHECK-GEN-ISEL-TRUE ; RUN: llc -verify-machineinstrs -O2 -ppc-asm-full-reg-names -mcpu=pwr7 -ppc-gen-isel=false < %s | FileCheck %s --implicit-check-not isel @.str = private unnamed_addr constant [3 x i8] c"]]\00", align 1 @.str.1 = private unnamed_addr constant [35 x i8] c"Index < Length && \22Invalid index!\22\00", align 1 @.str.2 = private unnamed_addr constant [50 x i8] c"/home/jtony/src/llvm/include/llvm/ADT/StringRef.h\00", align 1 @__PRETTY_FUNCTION__._ZNK4llvm9StringRefixEm = private unnamed_addr constant [47 x i8] c"char llvm::StringRef::operator[](size_t) const\00", align 1 @.str.3 = private unnamed_addr constant [95 x i8] c"(data || length == 0) && \22StringRef cannot be built from a NULL argument with non-null length\22\00", align 1 @__PRETTY_FUNCTION__._ZN4llvm9StringRefC2EPKcm = private unnamed_addr constant [49 x i8] c"llvm::StringRef::StringRef(const char *, size_t)\00", align 1 define i64 @_Z3fn1N4llvm9StringRefE([2 x i64] %Str.coerce) { entry: %Str.coerce.fca.0.extract = extractvalue [2 x i64] %Str.coerce, 0 %Str.coerce.fca.1.extract = extractvalue [2 x i64] %Str.coerce, 1 br label %while.cond.outer while.cond.outer: %Str.sroa.0.0.ph = phi i64 [ %8, %_ZNK4llvm9StringRef6substrEmm.exit ], [ %Str.coerce.fca.0.extract, %entry ] %.sink.ph = phi i64 [ %sub.i, %_ZNK4llvm9StringRef6substrEmm.exit ], [ %Str.coerce.fca.1.extract, %entry ] %BracketDepth.0.ph = phi i64 [ %BracketDepth.1, %_ZNK4llvm9StringRef6substrEmm.exit ], [ undef, %entry ] %cmp65 = icmp eq i64 %BracketDepth.0.ph, 0 br i1 %cmp65, label %while.cond.us.preheader, label %while.cond.preheader while.cond.us.preheader: br label %while.cond.us while.cond.preheader: %cmp.i34129 = icmp eq i64 %.sink.ph, 0 br i1 %cmp.i34129, label %cond.false.i.loopexit135, label %_ZNK4llvm9StringRefixEm.exit.preheader _ZNK4llvm9StringRefixEm.exit.preheader: br label %_ZNK4llvm9StringRefixEm.exit while.cond.us: %Str.sroa.0.0.us = phi i64 [ %3, %_ZNK4llvm9StringRef6substrEmm.exit50.us ], [ %Str.sroa.0.0.ph, %while.cond.us.preheader ] %.sink.us = phi i64 [ %sub.i41.us, %_ZNK4llvm9StringRef6substrEmm.exit50.us ], [ %.sink.ph, %while.cond.us.preheader ] %cmp.i30.us = icmp ult i64 %.sink.us, 2 br i1 %cmp.i30.us, label %if.end.us, label %if.end.i.i.us if.end.i.i.us: %0 = inttoptr i64 %Str.sroa.0.0.us to i8* %call.i.i.us = tail call signext i32 @memcmp(i8* %0, i8* getelementptr inbounds ([3 x i8], [3 x i8]* @.str, i64 0, i64 0), i64 2) %phitmp.i.us = icmp eq i32 %call.i.i.us, 0 br i1 %phitmp.i.us, label %if.then, label %_ZNK4llvm9StringRefixEm.exit.us if.end.us: %cmp.i34.us = icmp eq i64 %.sink.us, 0 br i1 %cmp.i34.us, label %cond.false.i.loopexit, label %_ZNK4llvm9StringRefixEm.exit.us _ZNK4llvm9StringRefixEm.exit.us: %1 = inttoptr i64 %Str.sroa.0.0.us to i8* %2 = load i8, i8* %1, align 1 switch i8 %2, label %_ZNK4llvm9StringRef6substrEmm.exit.loopexit [ i8 92, label %if.then4.us i8 93, label %if.then9 ] if.then4.us: %.sroa.speculated12.i38.us = select i1 %cmp.i30.us, i64 %.sink.us, i64 2 %add.ptr.i40.us = getelementptr inbounds i8, i8* %1, i64 %.sroa.speculated12.i38.us %sub.i41.us = sub i64 %.sink.us, %.sroa.speculated12.i38.us %tobool.i.i44.us = icmp ne i8* %add.ptr.i40.us, null %cmp.i4.i45.us = icmp eq i64 %sub.i41.us, 0 %or.cond.i.i46.us = or i1 %tobool.i.i44.us, %cmp.i4.i45.us br i1 %or.cond.i.i46.us, label %_ZNK4llvm9StringRef6substrEmm.exit50.us, label %cond.false.i.i47.loopexit _ZNK4llvm9StringRef6substrEmm.exit50.us: %3 = ptrtoint i8* %add.ptr.i40.us to i64 br label %while.cond.us if.then: ret i64 undef cond.false.i.loopexit: br label %cond.false.i cond.false.i.loopexit134: br label %cond.false.i cond.false.i.loopexit135: br label %cond.false.i cond.false.i: tail call void @__assert_fail(i8* getelementptr inbounds ([35 x i8], [35 x i8]* @.str.1, i64 0, i64 0), i8* getelementptr inbounds ([50 x i8], [50 x i8]* @.str.2, i64 0, i64 0), i32 zeroext 225, i8* getelementptr inbounds ([47 x i8], [47 x i8]* @__PRETTY_FUNCTION__._ZNK4llvm9StringRefixEm, i64 0, i64 0)) unreachable _ZNK4llvm9StringRefixEm.exit: %.sink131 = phi i64 [ %sub.i41, %_ZNK4llvm9StringRef6substrEmm.exit50 ], [ %.sink.ph, %_ZNK4llvm9StringRefixEm.exit.preheader ] %Str.sroa.0.0130 = phi i64 [ %6, %_ZNK4llvm9StringRef6substrEmm.exit50 ], [ %Str.sroa.0.0.ph, %_ZNK4llvm9StringRefixEm.exit.preheader ] %4 = inttoptr i64 %Str.sroa.0.0130 to i8* %5 = load i8, i8* %4, align 1 switch i8 %5, label %_ZNK4llvm9StringRef6substrEmm.exit.loopexit132 [ i8 92, label %if.then4 i8 93, label %if.end10 ] if.then4: %cmp.i.i37 = icmp ult i64 %.sink131, 2 %.sroa.speculated12.i38 = select i1 %cmp.i.i37, i64 %.sink131, i64 2 %add.ptr.i40 = getelementptr inbounds i8, i8* %4, i64 %.sroa.speculated12.i38 %sub.i41 = sub i64 %.sink131, %.sroa.speculated12.i38 %tobool.i.i44 = icmp ne i8* %add.ptr.i40, null %cmp.i4.i45 = icmp eq i64 %sub.i41, 0 %or.cond.i.i46 = or i1 %tobool.i.i44, %cmp.i4.i45 br i1 %or.cond.i.i46, label %_ZNK4llvm9StringRef6substrEmm.exit50, label %cond.false.i.i47.loopexit133 cond.false.i.i47.loopexit: br label %cond.false.i.i47 cond.false.i.i47.loopexit133: br label %cond.false.i.i47 cond.false.i.i47: tail call void @__assert_fail(i8* getelementptr inbounds ([95 x i8], [95 x i8]* @.str.3, i64 0, i64 0), i8* getelementptr inbounds ([50 x i8], [50 x i8]* @.str.2, i64 0, i64 0), i32 zeroext 90, i8* getelementptr inbounds ([49 x i8], [49 x i8]* @__PRETTY_FUNCTION__._ZN4llvm9StringRefC2EPKcm, i64 0, i64 0)) unreachable _ZNK4llvm9StringRef6substrEmm.exit50: %6 = ptrtoint i8* %add.ptr.i40 to i64 %cmp.i34 = icmp eq i64 %sub.i41, 0 br i1 %cmp.i34, label %cond.false.i.loopexit134, label %_ZNK4llvm9StringRefixEm.exit if.then9: tail call void @exit(i32 signext 1) unreachable if.end10: %dec = add i64 %BracketDepth.0.ph, -1 br label %_ZNK4llvm9StringRef6substrEmm.exit _ZNK4llvm9StringRef6substrEmm.exit.loopexit: br label %_ZNK4llvm9StringRef6substrEmm.exit _ZNK4llvm9StringRef6substrEmm.exit.loopexit132: br label %_ZNK4llvm9StringRef6substrEmm.exit _ZNK4llvm9StringRef6substrEmm.exit: %.sink76 = phi i64 [ %.sink131, %if.end10 ], [ %.sink.us, %_ZNK4llvm9StringRef6substrEmm.exit.loopexit ], [ %.sink131, %_ZNK4llvm9StringRef6substrEmm.exit.loopexit132 ] %7 = phi i8* [ %4, %if.end10 ], [ %1, %_ZNK4llvm9StringRef6substrEmm.exit.loopexit ], [ %4, %_ZNK4llvm9StringRef6substrEmm.exit.loopexit132 ] %BracketDepth.1 = phi i64 [ %dec, %if.end10 ], [ 0, %_ZNK4llvm9StringRef6substrEmm.exit.loopexit ], [ %BracketDepth.0.ph, %_ZNK4llvm9StringRef6substrEmm.exit.loopexit132 ] %sub.i = add i64 %.sink76, -1 %add.ptr.i = getelementptr inbounds i8, i8* %7, i64 1 %8 = ptrtoint i8* %add.ptr.i to i64 br label %while.cond.outer ; CHECK-LABEL: @_Z3fn1N4llvm9StringRefE ; Unecessary ISEL (all the registers are the same) is always removed ; CHECK-GEN-ISEL-TRUE-NOT: isel [[SAME:r[0-9]+]], [[SAME]], [[SAME]] ; CHECK-GEN-ISEL-TRUE: isel [[SAME:r[0-9]+]], {{r[0-9]+}}, [[SAME]] ; CHECK: bc 12, eq, [[TRUE:.LBB[0-9]+]] ; CHECK-NEXT: b [[SUCCESSOR:.LBB[0-9]+]] ; CHECK-NEXT: [[TRUE]] ; CHECK-NEXT: addi {{r[0-9]+}}, {{r[0-9]+}}, 0 ; CHECK-NEXT: [[SUCCESSOR]] } declare void @exit(i32 signext) declare signext i32 @memcmp(i8* nocapture, i8* nocapture, i64) declare void @__assert_fail(i8*, i8*, i32 zeroext, i8*)