From db14d63ceac6d667dc1669d199c01a8d3246203c Mon Sep 17 00:00:00 2001 From: Bill Wendling Date: Mon, 16 Mar 2009 20:27:20 +0000 Subject: [PATCH] --- Reverse-merging (from foreign repository) r67049 into '.': U test/CodeGen/X86/2009-03-13-PHIElimBug.ll D test/CodeGen/X86/2009-03-16-PHIElimInLPad.ll U lib/CodeGen/PHIElimination.cpp r67049 was causing this failure: Running /Volumes/Sandbox/Buildbot/llvm/full-llvm/build/llvm.src/test/CodeGen/X86/dg.exp ... FAIL: /Volumes/Sandbox/Buildbot/llvm/full-llvm/build/llvm.src/test/CodeGen/X86/2009-03-13-PHIElimBug.ll for PR3784 Failed with exit(1) at line 1 while running: llvm-as < /Volumes/Sandbox/Buildbot/llvm/full-llvm/build/llvm.src/test/CodeGen/X86/2009-03-13-PHIElimBug.ll | llc -march=x86 | /usr/bin/grep -A 2 {call f} | /usr/bin/grep movl child process exited abnormally git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@67051 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/CodeGen/PHIElimination.cpp | 100 ++++++++----------- test/CodeGen/X86/2009-03-13-PHIElimBug.ll | 55 +++++----- test/CodeGen/X86/2009-03-16-PHIElimInLPad.ll | 21 ---- 3 files changed, 71 insertions(+), 105 deletions(-) delete mode 100644 test/CodeGen/X86/2009-03-16-PHIElimInLPad.ll diff --git a/lib/CodeGen/PHIElimination.cpp b/lib/CodeGen/PHIElimination.cpp index 67c555fd17f..6f3c82c7081 100644 --- a/lib/CodeGen/PHIElimination.cpp +++ b/lib/CodeGen/PHIElimination.cpp @@ -14,8 +14,6 @@ //===----------------------------------------------------------------------===// #define DEBUG_TYPE "phielim" -#include "llvm/BasicBlock.h" -#include "llvm/Instructions.h" #include "llvm/CodeGen/LiveVariables.h" #include "llvm/CodeGen/Passes.h" #include "llvm/CodeGen/MachineFunctionPass.h" @@ -33,6 +31,7 @@ using namespace llvm; STATISTIC(NumAtomic, "Number of atomic phis lowered"); +STATISTIC(NumEH, "Number of EH try blocks skipped"); namespace { class VISIBILITY_HIDDEN PNE : public MachineFunctionPass { @@ -67,25 +66,8 @@ namespace { /// void analyzePHINodes(const MachineFunction& Fn); - // FindCopyInsertPoint - Find a safe place in MBB to insert a copy from - // SrcReg. This needs to be after any def or uses of SrcReg, but before - // any subsequent point where control flow might jump out of the basic - // block. - MachineBasicBlock::iterator FindCopyInsertPoint(MachineBasicBlock &MBB, - unsigned SrcReg); - - // SkipPHIsAndLabels - Copies need to be inserted after phi nodes and - // also after any exception handling labels: in landing pads execution - // starts at the label, so any copies placed before it won't be executed! - MachineBasicBlock::iterator SkipPHIsAndLabels(MachineBasicBlock &MBB, - MachineBasicBlock::iterator I) { - // Rather than assuming that EH labels come before other kinds of labels, - // just skip all labels. - while (I != MBB.end() && - (I->getOpcode() == TargetInstrInfo::PHI || I->isLabel())) - ++I; - return I; - } + void WalkPassEHTryRange(MachineBasicBlock &MBB, + MachineBasicBlock::iterator &I, unsigned SrcReg); typedef std::pair BBVRegPair; typedef std::map VRegPHIUse; @@ -138,7 +120,10 @@ bool PNE::EliminatePHINodes(MachineFunction &MF, MachineBasicBlock &MBB) { // Get an iterator to the first instruction after the last PHI node (this may // also be the end of the basic block). - MachineBasicBlock::iterator AfterPHIsIt = SkipPHIsAndLabels(MBB, MBB.begin()); + MachineBasicBlock::iterator AfterPHIsIt = MBB.begin(); + while (AfterPHIsIt != MBB.end() && + AfterPHIsIt->getOpcode() == TargetInstrInfo::PHI) + ++AfterPHIsIt; // Skip over all of the PHI nodes... while (MBB.front().getOpcode() == TargetInstrInfo::PHI) LowerAtomicPHINode(MBB, AfterPHIsIt); @@ -159,47 +144,37 @@ static bool isSourceDefinedByImplicitDef(const MachineInstr *MPhi, return true; } -// FindCopyInsertPoint - Find a safe place in MBB to insert a copy from SrcReg. -// This needs to be after any def or uses of SrcReg, but before any subsequent -// point where control flow might jump out of the basic block. -MachineBasicBlock::iterator PNE::FindCopyInsertPoint(MachineBasicBlock &MBB, - unsigned SrcReg) { - // Handle the trivial case trivially. - if (MBB.empty()) - return MBB.begin(); - - // If this basic block does not contain an invoke, then control flow always - // reaches the end of it, so place the copy there. The logic below works in - // this case too, but is more expensive. - if (!isa(MBB.getBasicBlock()->getTerminator())) - return MBB.getFirstTerminator(); - - // Discover any definition/uses in this basic block. - SmallPtrSet DefUsesInMBB; - for (MachineRegisterInfo::reg_iterator RI = MRI->reg_begin(SrcReg), - RE = MRI->reg_end(); RI != RE; ++RI) { - MachineInstr *DefUseMI = &*RI; - if (DefUseMI->getParent() == &MBB) - DefUsesInMBB.insert(DefUseMI); +void PNE::WalkPassEHTryRange(MachineBasicBlock &MBB, + MachineBasicBlock::iterator &I, unsigned SrcReg) { + if (I == MBB.begin()) + return; + MachineBasicBlock::iterator PI = prior(I); + if (PI->getOpcode() != TargetInstrInfo::EH_LABEL) + return; + + // Trying to walk pass the EH try range. If we run into a use instruction, + // we want to insert the copy there. + SmallPtrSet UsesInMBB; + for (MachineRegisterInfo::use_iterator UI = MRI->use_begin(SrcReg), + UE = MRI->use_end(); UI != UE; ++UI) { + MachineInstr *UseMI = &*UI; + if (UseMI->getParent() == &MBB) + UsesInMBB.insert(UseMI); } - MachineBasicBlock::iterator InsertPoint; - if (DefUsesInMBB.empty()) { - // No def/uses. Insert the copy at the start of the basic block. - InsertPoint = MBB.begin(); - } else if (DefUsesInMBB.size() == 1) { - // Insert the copy immediately after the definition/use. - InsertPoint = *DefUsesInMBB.begin(); - ++InsertPoint; - } else { - // Insert the copy immediately after the last definition/use. - InsertPoint = MBB.end(); - while (!DefUsesInMBB.count(&*--InsertPoint)) {} - ++InsertPoint; + while (PI != MBB.begin()) { + --PI; + if (PI->getOpcode() == TargetInstrInfo::EH_LABEL) { + ++NumEH; + I = PI; + return; + } else if (UsesInMBB.count(&*PI)) { + ++NumEH; + I = next(PI); + return; + } } - - // Make sure the copy goes after any phi nodes however. - return SkipPHIsAndLabels(MBB, InsertPoint); + return; } /// LowerAtomicPHINode - Lower the PHI node at the top of the specified block, @@ -298,7 +273,10 @@ void PNE::LowerAtomicPHINode(MachineBasicBlock &MBB, // Find a safe location to insert the copy, this may be the first terminator // in the block (or end()). - MachineBasicBlock::iterator InsertPos = FindCopyInsertPoint(opBlock, SrcReg); + MachineBasicBlock::iterator InsertPos = opBlock.getFirstTerminator(); + + // Walk pass EH try range if needed. + WalkPassEHTryRange(opBlock, InsertPos, SrcReg); // Insert the copy. TII->copyRegToReg(opBlock, InsertPos, IncomingReg, SrcReg, RC, RC); diff --git a/test/CodeGen/X86/2009-03-13-PHIElimBug.ll b/test/CodeGen/X86/2009-03-13-PHIElimBug.ll index 546fdbf1391..ea4150c22c2 100644 --- a/test/CodeGen/X86/2009-03-13-PHIElimBug.ll +++ b/test/CodeGen/X86/2009-03-13-PHIElimBug.ll @@ -1,28 +1,37 @@ -; RUN: llvm-as < %s | llc -march=x86 | grep -A 2 {call f} | grep movl -; Check the register copy comes after the call to f and before the call to g +; RUN: llvm-as < %s | llc -mtriple=i386-pc-linux-gnu -stats |& grep phielim | grep {Number of EH try blocks skipped} | grep 4 ; PR3784 -declare i32 @f() + %struct.c38002a__arr___XUB = type { i32, i32 } + %struct.c38002a__arr_name = type { [0 x i32]*, %struct.c38002a__arr___XUB* } + %struct.c38002a__rec = type { i32, %struct.c38002a__arr_name } -declare i32 @g() - -define i32 @phi() { +define void @_ada_c38002a() { entry: - %a = call i32 @f() ; [#uses=1] - %b = invoke i32 @g() - to label %cont unwind label %lpad ; [#uses=1] - -cont: ; preds = %entry - %x = phi i32 [ %b, %entry ] ; [#uses=0] - %aa = call i32 @g() ; [#uses=1] - %bb = invoke i32 @g() - to label %cont2 unwind label %lpad ; [#uses=1] - -cont2: ; preds = %cont - %xx = phi i32 [ %bb, %cont ] ; [#uses=1] - ret i32 %xx - -lpad: ; preds = %cont, %entry - %y = phi i32 [ %a, %entry ], [ %aa, %cont ] ; [#uses=1] - ret i32 %y + %0 = invoke i8* @__gnat_malloc(i32 12) + to label %invcont unwind label %lpad ; [#uses=0] + +invcont: ; preds = %entry + %1 = invoke i8* @__gnat_malloc(i32 20) + to label %invcont1 unwind label %lpad ; [#uses=0] + +invcont1: ; preds = %invcont + %2 = invoke i32 @report__ident_int(i32 2) + to label %.noexc unwind label %lpad ; [#uses=0] + +.noexc: ; preds = %invcont1 + %3 = invoke i32 @report__ident_int(i32 3) + to label %.noexc88 unwind label %lpad ; [#uses=0] + +.noexc88: ; preds = %.noexc + unreachable + +lpad: ; preds = %.noexc, %invcont1, %invcont, %entry + %r.0 = phi %struct.c38002a__rec* [ null, %entry ], [ null, %invcont ], [ null, %invcont1 ], [ null, %.noexc ] ; <%struct.c38002a__rec*> [#uses=1] + %4 = getelementptr %struct.c38002a__rec* %r.0, i32 0, i32 0 ; [#uses=1] + %5 = load i32* %4, align 4 ; [#uses=0] + ret void } + +declare i32 @report__ident_int(i32) + +declare i8* @__gnat_malloc(i32) diff --git a/test/CodeGen/X86/2009-03-16-PHIElimInLPad.ll b/test/CodeGen/X86/2009-03-16-PHIElimInLPad.ll deleted file mode 100644 index c079ae73725..00000000000 --- a/test/CodeGen/X86/2009-03-16-PHIElimInLPad.ll +++ /dev/null @@ -1,21 +0,0 @@ -; RUN: llvm-as < %s | llc -march=x86 | grep -A 1 lpad | grep Llabel -; Check that register copies in the landing pad come after the EH_LABEL - -declare i32 @f() - -define i32 @phi(i32 %x) { -entry: - %a = invoke i32 @f() - to label %cont unwind label %lpad ; [#uses=1] - -cont: ; preds = %entry - %b = invoke i32 @f() - to label %cont2 unwind label %lpad ; [#uses=1] - -cont2: ; preds = %cont - ret i32 %b - -lpad: ; preds = %cont, %entry - %v = phi i32 [ %x, %entry ], [ %a, %cont ] ; [#uses=1] - ret i32 %v -} -- 2.34.1