From ad966559057ad30a77dccb47d85646d4c621a31c Mon Sep 17 00:00:00 2001
From: Hal Finkel <hfinkel@anl.gov>
Date: Sun, 12 Apr 2015 17:18:56 +0000
Subject: [PATCH] [PowerPC] Really iterate over all loops in
 PPCLoopDataPrefetch/PPCLoopPreIncPrep

When I fixed these a couple of days ago to iterate over all loops, not just
depth == 1 loops, I inadvertently made it such that we'd only look at the first
top-level loop. Make sure that we really look at all of them.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@234705 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Target/PowerPC/PPCLoopDataPrefetch.cpp | 10 ++---
 lib/Target/PowerPC/PPCLoopPreIncPrep.cpp   | 10 ++---
 test/CodeGen/PowerPC/loop-prep-all.ll      | 48 ++++++++++++++++++++++
 3 files changed, 54 insertions(+), 14 deletions(-)
 create mode 100644 test/CodeGen/PowerPC/loop-prep-all.ll

diff --git a/lib/Target/PowerPC/PPCLoopDataPrefetch.cpp b/lib/Target/PowerPC/PPCLoopDataPrefetch.cpp
index 77d3727c303..2947c6617bd 100644
--- a/lib/Target/PowerPC/PPCLoopDataPrefetch.cpp
+++ b/lib/Target/PowerPC/PPCLoopDataPrefetch.cpp
@@ -111,13 +111,9 @@ bool PPCLoopDataPrefetch::runOnFunction(Function &F) {
 
   bool MadeChange = false;
 
-  if (LI->empty())
-    return MadeChange;
-
-  for (auto I = df_begin(*LI->begin()), E = df_end(*LI->begin()); I != E; ++I) {
-    Loop *L = *I;
-    MadeChange |= runOnLoop(L);
-  }
+  for (auto I = LI->begin(), IE = LI->end(); I != IE; ++I)
+    for (auto L = df_begin(*I), LE = df_end(*I); L != LE; ++L)
+      MadeChange |= runOnLoop(*L);
 
   return MadeChange;
 }
diff --git a/lib/Target/PowerPC/PPCLoopPreIncPrep.cpp b/lib/Target/PowerPC/PPCLoopPreIncPrep.cpp
index 41cc15ab419..b6e7799402e 100644
--- a/lib/Target/PowerPC/PPCLoopPreIncPrep.cpp
+++ b/lib/Target/PowerPC/PPCLoopPreIncPrep.cpp
@@ -144,13 +144,9 @@ bool PPCLoopPreIncPrep::runOnFunction(Function &F) {
 
   bool MadeChange = false;
 
-  if (LI->empty())
-    return MadeChange;
-
-  for (auto I = df_begin(*LI->begin()), E = df_end(*LI->begin()); I != E; ++I) {
-    Loop *L = *I;
-    MadeChange |= runOnLoop(L);
-  }
+  for (auto I = LI->begin(), IE = LI->end(); I != IE; ++I)
+    for (auto L = df_begin(*I), LE = df_end(*I); L != LE; ++L)
+      MadeChange |= runOnLoop(*L);
 
   return MadeChange;
 }
diff --git a/test/CodeGen/PowerPC/loop-prep-all.ll b/test/CodeGen/PowerPC/loop-prep-all.ll
new file mode 100644
index 00000000000..895daff63ad
--- /dev/null
+++ b/test/CodeGen/PowerPC/loop-prep-all.ll
@@ -0,0 +1,48 @@
+; RUN: llc < %s | FileCheck %s
+; RUN: llc -mtriple=powerpc64-bgq-linux < %s | FileCheck %s -check-prefix=CHECK -check-prefix=CHECK-BGQ
+target datalayout = "E-m:e-i64:64-n32:64"
+target triple = "powerpc64-unknown-linux-gnu"
+
+; Function Attrs: nounwind
+define void @foo(double* nocapture %x, double* nocapture readonly %y) #0 {
+entry:
+  br label %for.body
+
+for.body:                                         ; preds = %for.body, %entry
+  %indvars.iv = phi i64 [ 0, %entry ], [ %indvars.iv.next, %for.body ]
+  %arrayidx = getelementptr inbounds double, double* %y, i64 %indvars.iv
+  %0 = load double, double* %arrayidx, align 8
+  %add = fadd double %0, 1.000000e+00
+  %arrayidx2 = getelementptr inbounds double, double* %x, i64 %indvars.iv
+  store double %add, double* %arrayidx2, align 8
+  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
+  %exitcond19 = icmp eq i64 %indvars.iv.next, 1600
+  br i1 %exitcond19, label %for.body7, label %for.body
+
+; CHECK-LABEL: @foo
+
+; CHECK-BGQ-DAG: dcbt 4, 5
+; CHECK-DAG: lfdu [[REG1:[0-9]+]], 8({{[0-9]+}})
+; CHECK-DAG: fadd [[REG2:[0-9]+]], [[REG1]], 0
+; CHECK-DAG: stfdu [[REG2]], 8({{[0-9]+}})
+; CHECK: bdnz
+
+; CHECK: blr
+
+for.cond.cleanup6:                                ; preds = %for.body7
+  ret void
+
+for.body7:                                        ; preds = %for.body, %for.body7
+  %i3.017 = phi i32 [ %inc9, %for.body7 ], [ 0, %for.body ]
+  tail call void bitcast (void (...)* @bar to void ()*)() #2
+  %inc9 = add nuw nsw i32 %i3.017, 1
+  %exitcond = icmp eq i32 %inc9, 1024
+  br i1 %exitcond, label %for.cond.cleanup6, label %for.body7
+}
+
+declare void @bar(...) #1
+
+attributes #0 = { nounwind "target-cpu"="a2q" }
+attributes #1 = { "target-cpu"="a2q" }
+attributes #2 = { nounwind }
+
-- 
2.34.1