fix minsize detection: minsize attribute implies optimizing for size

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@244617 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Transforms/Vectorize/LoopVectorize.cpp

@@ -1719,8 +1719,7 @@ struct LoopVectorize : public FunctionPass {
     // Check the function attributes to find out if this function should be
     // optimized for size.
     bool OptForSize = Hints.getForce() != LoopVectorizeHints::FK_Enabled &&
-                      // FIXME: Use Function::optForSize().
-                      F->hasFnAttribute(Attribute::OptimizeForSize);
+                      F->optForSize();
 
     // Compute the weighted frequency of this loop being executed and see if it
     // is less than 20% of the function entry baseline frequency. Note that we
@@ -4614,8 +4613,9 @@ LoopVectorizationCostModel::selectVectorizationFactor(bool OptForSize) {
     emitAnalysis(VectorizationReport() <<
                  "runtime pointer checks needed. Enable vectorization of this "
                  "loop with '#pragma clang loop vectorize(enable)' when "
-                 "compiling with -Os");
-    DEBUG(dbgs() << "LV: Aborting. Runtime ptr check is required in Os.\n");
+                 "compiling with -Os/-Oz");
+    DEBUG(dbgs() <<
+          "LV: Aborting. Runtime ptr check is required with -Os/-Oz.\n");
     return Factor;
   }
 
@@ -4659,7 +4659,7 @@ LoopVectorizationCostModel::selectVectorizationFactor(bool OptForSize) {
       emitAnalysis
         (VectorizationReport() <<
          "unable to calculate the loop count due to complex control flow");
-      DEBUG(dbgs() << "LV: Aborting. A tail loop is required in Os.\n");
+      DEBUG(dbgs() << "LV: Aborting. A tail loop is required with -Os/-Oz.\n");
       return Factor;
     }
 
@@ -4675,8 +4675,8 @@ LoopVectorizationCostModel::selectVectorizationFactor(bool OptForSize) {
                    "cannot optimize for size and vectorize at the "
                    "same time. Enable vectorization of this loop "
                    "with '#pragma clang loop vectorize(enable)' "
-                   "when compiling with -Os");
-      DEBUG(dbgs() << "LV: Aborting. A tail loop is required in Os.\n");
+                   "when compiling with -Os/-Oz");
+      DEBUG(dbgs() << "LV: Aborting. A tail loop is required with -Os/-Oz.\n");
       return Factor;
     }
   }

test/Transforms/LoopVectorize/optsize.ll

@@ -1,17 +1,17 @@
 ; This test verifies that the loop vectorizer will NOT produce a tail
-; loop with Optimize for size attibute.
+; loop with the optimize for size or the minimize size attributes.
 ; REQUIRES: asserts
-; RUN: opt < %s -loop-vectorize -debug -debug-only=loop-vectorize -S 2>&1 | FileCheck %s
-
-; CHECK-NOT: <2 x i8>
-; CHECK-NOT: <4 x i8>
-; CHECK: Aborting. A tail loop is required in Os.
+; RUN: opt < %s -loop-vectorize -S | FileCheck %s
 
 target datalayout = "E-m:e-p:32:32-i64:32-f64:32:64-a:0:32-n32-S128"
 
 @tab = common global [32 x i8] zeroinitializer, align 1
 
-define i32 @foo() #0 {
+define i32 @foo_optsize() #0 {
+; CHECK-LABEL: @foo_optsize(
+; CHECK-NOT: <2 x i8>
+; CHECK-NOT: <4 x i8>
+
 entry:
   br label %for.body
 
@@ -32,3 +32,28 @@ for.end:                                          ; preds = %for.body
 
 attributes #0 = { optsize }
 
+define i32 @foo_minsize() #1 {
+; CHECK-LABEL: @foo_minsize(
+; CHECK-NOT: <2 x i8>
+; CHECK-NOT: <4 x i8>
+
+entry:
+  br label %for.body
+
+for.body:                                         ; preds = %for.body, %entry
+  %i.08 = phi i32 [ 0, %entry ], [ %inc, %for.body ]
+  %arrayidx = getelementptr inbounds [32 x i8], [32 x i8]* @tab, i32 0, i32 %i.08
+  %0 = load i8, i8* %arrayidx, align 1
+  %cmp1 = icmp eq i8 %0, 0
+  %. = select i1 %cmp1, i8 2, i8 1
+  store i8 %., i8* %arrayidx, align 1
+  %inc = add nsw i32 %i.08, 1
+  %exitcond = icmp eq i32 %i.08, 202
+  br i1 %exitcond, label %for.end, label %for.body
+
+for.end:                                          ; preds = %for.body
+  ret i32 0
+}
+
+attributes #1 = { minsize }
+