From e09206d4d7683e2a421104c5cb83f7808ba4b06e Mon Sep 17 00:00:00 2001
From: Evan Cheng <evan.cheng@apple.com>
Date: Fri, 29 Oct 2010 23:16:55 +0000
Subject: [PATCH] Fix fpscr <-> GPR latency info.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@117737 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Target/ARM/ARMBaseInstrInfo.cpp | 11 +++++++++--
 lib/Target/ARM/ARMScheduleA8.td     |  2 +-
 lib/Target/ARM/ARMScheduleA9.td     |  3 ++-
 3 files changed, 12 insertions(+), 4 deletions(-)

diff --git a/lib/Target/ARM/ARMBaseInstrInfo.cpp b/lib/Target/ARM/ARMBaseInstrInfo.cpp
index c23bc93925b..d4b832e7bc6 100644
--- a/lib/Target/ARM/ARMBaseInstrInfo.cpp
+++ b/lib/Target/ARM/ARMBaseInstrInfo.cpp
@@ -1914,9 +1914,16 @@ ARMBaseInstrInfo::getOperandLatency(const InstrItineraryData *ItinData,
 
   const TargetInstrDesc &UseTID = UseMI->getDesc();
   const MachineOperand &DefMO = DefMI->getOperand(DefIdx);
-  if (DefMO.getReg() == ARM::CPSR && UseTID.isBranch())
+  if (DefMO.getReg() == ARM::CPSR) {
+    if (DefMI->getOpcode() == ARM::FMSTAT) {
+      // fpscr -> cpsr stalls over 20 cycles on A8 (and earlier?)
+      return Subtarget.isCortexA9() ? 1 : 20;
+    }
+
     // CPSR set and branch can be paired in the same cycle.
-    return 0;
+    if (UseTID.isBranch())
+      return 0;
+  }
 
   unsigned DefAlign = DefMI->hasOneMemOperand()
     ? (*DefMI->memoperands_begin())->getAlignment() : 0;
diff --git a/lib/Target/ARM/ARMScheduleA8.td b/lib/Target/ARM/ARMScheduleA8.td
index 32d9d66837b..1f19b21e1c3 100644
--- a/lib/Target/ARM/ARMScheduleA8.td
+++ b/lib/Target/ARM/ARMScheduleA8.td
@@ -237,7 +237,7 @@ def CortexA8Itineraries : ProcessorItineraries<
   //
   // FP Special Register to Integer Register File Move
   InstrItinData<IIC_fpSTAT , [InstrStage<1, [A8_Pipe0, A8_Pipe1]>,
-                              InstrStage<1, [A8_NLSPipe]>]>,
+                              InstrStage<1, [A8_NLSPipe]>], [20]>,
   //
   // Single-precision FP Unary
   InstrItinData<IIC_fpUNA32 , [InstrStage<1, [A8_Pipe0, A8_Pipe1]>,
diff --git a/lib/Target/ARM/ARMScheduleA9.td b/lib/Target/ARM/ARMScheduleA9.td
index 20aa64163bf..3096b0ad990 100644
--- a/lib/Target/ARM/ARMScheduleA9.td
+++ b/lib/Target/ARM/ARMScheduleA9.td
@@ -431,7 +431,8 @@ def CortexA9Itineraries : ProcessorItineraries<
                               InstrStage<1, [A9_MUX0], 0>,
                               InstrStage<1, [A9_DRegsVFP], 0, Required>,
                               InstrStage<2, [A9_DRegsN],   0, Reserved>,
-                              InstrStage<1, [A9_NPipe]>]>,
+                              InstrStage<1, [A9_NPipe]>],
+                             [1]>,
   //
   // Single-precision FP Unary
   InstrItinData<IIC_fpUNA32 , [InstrStage<1, [A9_Issue0, A9_Issue1], 0>,
-- 
2.34.1