Index: lib/Target/PowerPC/PPCCTRLoops.cpp =================================================================== --- lib/Target/PowerPC/PPCCTRLoops.cpp +++ lib/Target/PowerPC/PPCCTRLoops.cpp @@ -194,6 +194,19 @@ return false; } +static bool memAddrUsesCTR(const PPCTargetMachine *TM, + const llvm::Value *MemAddr) { + const auto *GV = dyn_cast(MemAddr); + if (!GV) + return false; + if (!GV->isThreadLocal()) + return false; + if (!TM) + return true; + TLSModel::Model Model = TM->getTLSModel(GV); + return Model == TLSModel::GeneralDynamic || Model == TLSModel::LocalDynamic; +} + bool PPCCTRLoops::mightUseCTR(const Triple &TT, BasicBlock *BB) { for (BasicBlock::iterator J = BB->begin(), JE = BB->end(); J != JE; ++J) { @@ -389,6 +402,9 @@ if (SI->getNumCases() + 1 >= (unsigned)TLI->getMinimumJumpTableEntries()) return true; } + for (Value *Operand : J->operands()) + if (memAddrUsesCTR(TM, Operand)) + return true; } return false; Index: test/CodeGen/PowerPC/ctrloops.ll =================================================================== --- test/CodeGen/PowerPC/ctrloops.ll +++ test/CodeGen/PowerPC/ctrloops.ll @@ -1,6 +1,6 @@ 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-v128:128:128-n32:64" target triple = "powerpc64-unknown-freebsd10.0" -; RUN: llc < %s -march=ppc64 | FileCheck %s +; RUN: llc < %s -march=ppc64 -relocation-model=pic | FileCheck %s @a = common global i32 0, align 4 @@ -73,3 +73,26 @@ ; CHECK-NOT: cmplwi ; CHECK: bdnz } + +@tls_var = external thread_local global i8 + +define i32 @test4() { +entry: + br label %for.body + +for.body: ; preds = %for.body, %entry + %phi = phi i32 [ %dec, %for.body ], [ undef, %entry ] + %load = ptrtoint i8* @tls_var to i32 + %dec = add i32 %phi, -1 + %cmp = icmp sgt i32 %phi, 1 + br i1 %cmp, label %for.body, label %return + +return: ; preds = %for.body + ret i32 %load +; CHECK-LABEL: @test4 +; CHECK-NOT: mtctr +; CHECK: addi {{[0-9]+}} +; CHECK: cmpwi +; CHECK-NOT: bdnz +; CHECK: bgt +}