[llvm] r200616 - ARMTTI: We don't have 16 allocatable scalar registers

[Arnold Schwaighofer]

Author: arnolds
Date: Sat Feb  1 12:00:25 2014
New Revision: 200616

URL: http://llvm.org/viewvc/llvm-project?rev=200616&view=rev
Log:
ARMTTI: We don't have 16 allocatable scalar registers

This caused an regression on libquantum after enabling the new loop vectorizer
unroll heuristics.

Modified:
    llvm/trunk/lib/Target/ARM/ARMTargetTransformInfo.cpp
    llvm/trunk/test/Transforms/LoopVectorize/ARM/arm-unroll.ll

Modified: llvm/trunk/lib/Target/ARM/ARMTargetTransformInfo.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/ARM/ARMTargetTransformInfo.cpp?rev=200616&r1=200615&r2=200616&view=diff
==============================================================================
--- llvm/trunk/lib/Target/ARM/ARMTargetTransformInfo.cpp (original)
+++ llvm/trunk/lib/Target/ARM/ARMTargetTransformInfo.cpp Sat Feb  1 12:00:25 2014
@@ -95,7 +95,7 @@ public:
 
     if (ST->isThumb1Only())
       return 8;
-    return 16;
+    return 13;
   }
 
   unsigned getRegisterBitWidth(bool Vector) const {

Modified: llvm/trunk/test/Transforms/LoopVectorize/ARM/arm-unroll.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/LoopVectorize/ARM/arm-unroll.ll?rev=200616&r1=200615&r2=200616&view=diff
==============================================================================
--- llvm/trunk/test/Transforms/LoopVectorize/ARM/arm-unroll.ll (original)
+++ llvm/trunk/test/Transforms/LoopVectorize/ARM/arm-unroll.ll Sat Feb  1 12:00:25 2014
@@ -1,5 +1,6 @@
 ; RUN: opt < %s  -loop-vectorize -mtriple=thumbv7-apple-ios3.0.0 -S | FileCheck %s
 ; RUN: opt < %s  -loop-vectorize -mtriple=thumbv7-apple-ios3.0.0 -mcpu=swift -S | FileCheck %s --check-prefix=SWIFT
+; RUN: opt < %s  -loop-vectorize -force-vector-width=1 -mtriple=thumbv7-apple-ios3.0.0 -mcpu=swift -S | FileCheck %s --check-prefix=SWIFTUNROLL
 
 target datalayout = "e-p:32:32:32-i1:8:32-i8:8:32-i16:16:32-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:32:64-v128:32:128-a0:0:32-n32-S32"
 target triple = "thumbv7-apple-ios3.0.0"
@@ -30,3 +31,38 @@ define i32 @foo(i32* nocapture %A, i32 %
   %sum.0.lcssa = phi i32 [ 0, %0 ], [ %4, %.lr.ph ]
   ret i32 %sum.0.lcssa
 }
+
+; Verify the register limit. On arm we don't have 16 allocatable registers.
+;SWIFTUNROLL-LABEL: @register_limit(
+;SWIFTUNROLL: load i32
+;SWIFTUNROLL-NOT: load i32
+define i32 @register_limit(i32* nocapture %A, i32 %n) {
+  %1 = icmp sgt i32 %n, 0
+  br i1 %1, label %.lr.ph, label %._crit_edge
+
+.lr.ph:
+  %i.02 = phi i32 [ %5, %.lr.ph ], [ 0, %0 ]
+  %sum.01 = phi i32 [ %4, %.lr.ph ], [ 0, %0 ]
+  %sum.02 = phi i32 [ %6, %.lr.ph ], [ 0, %0 ]
+  %sum.03 = phi i32 [ %7, %.lr.ph ], [ 0, %0 ]
+  %sum.04 = phi i32 [ %8, %.lr.ph ], [ 0, %0 ]
+  %sum.05 = phi i32 [ %9, %.lr.ph ], [ 0, %0 ]
+  %2 = getelementptr inbounds i32* %A, i32 %i.02
+  %3 = load i32* %2, align 4
+  %4 = add nsw i32 %3, %sum.01
+  %5 = add nsw i32 %i.02, 1
+  %6 = add nsw i32 %3, %sum.02
+  %7 = add nsw i32 %3, %sum.03
+  %8 = add nsw i32 %3, %sum.04
+  %9 = add nsw i32 %3, %sum.05
+  %exitcond = icmp eq i32 %5, %n
+  br i1 %exitcond, label %._crit_edge, label %.lr.ph
+
+._crit_edge:                                      ; preds = %.lr.ph, %0
+  %sum.0.lcssa = phi i32 [ 0, %0 ], [ %4, %.lr.ph ]
+  %sum.1.lcssa = phi i32 [ 0, %0 ], [ %6, %.lr.ph ]
+  %sum.2.lcssa = phi i32 [ 0, %0 ], [ %7, %.lr.ph ]
+  %sum.4.lcssa = phi i32 [ 0, %0 ], [ %8, %.lr.ph ]
+  %sum.5.lcssa = phi i32 [ 0, %0 ], [ %9, %.lr.ph ]
+  ret i32 %sum.0.lcssa
+}