[DAGCombine][ARM] Enable extending masked loads

Add generic DAG combine for extending masked loads.

Allow us to generate sext/zext masked loads which can access v4i8,
v8i8 and v4i16 memory to produce v4i32, v8i16 and v4i32 respectively.

Differential Revision: https://reviews.llvm.org/D68337

llvm-svn: 375085

1 files changed, 139 insertions, 3 deletions

diff --git a/llvm/test/Transforms/LoopVectorize/ARM/mve-maskedldst.ll b/llvm/test/Transforms/LoopVectorize/ARM/mve-maskedldst.ll
index 38d838576bd..5d30aba6782 100644
--- a/llvm/test/Transforms/LoopVectorize/ARM/mve-maskedldst.ll
+++ b/llvm/test/Transforms/LoopVectorize/ARM/mve-maskedldst.ll
@@ -3,9 +3,9 @@
 target datalayout = "e-m:e-p:32:32-Fi8-i64:64-v128:64:128-a:0:32-n32-S64"
 target triple = "thumbv8.1-m.main-none-eabi"
 
-; CHECK-LABEL: test
-; CHECK: llvm.masked.store.v4i32.p0v4i32
-define void @test(i32* nocapture %A, i32 %n) #0 {
+; CHECK-LABEL: test_i32_align4
+; CHECK: call void @llvm.masked.store.v4i32.p0v4i32
+define void @test_i32_align4(i32* nocapture %A, i32 %n) #0 {
 entry:
   %cmp12 = icmp sgt i32 %n, 0
   br i1 %cmp12, label %for.body.preheader, label %for.cond.cleanup
@@ -37,4 +37,140 @@ for.cond.cleanup:                                 ; preds = %for.cond.cleanup.lo
   ret void
 }
 
+; CHECK-LABEL: test_i32_align2
+; CHECK-NOT: call void @llvm.masked.store
+define void @test_i32_align2(i32* nocapture %A, i32 %n) #0 {
+entry:
+  %cmp12 = icmp sgt i32 %n, 0
+  br i1 %cmp12, label %for.body.preheader, label %for.cond.cleanup
+
+for.body.preheader:                               ; preds = %entry
+  br label %for.body
+
+for.body:                                         ; preds = %for.body.preheader, %for.inc
+  %i.013 = phi i32 [ %inc, %for.inc ], [ 0, %for.body.preheader ]
+  %arrayidx = getelementptr inbounds i32, i32* %A, i32 %i.013
+  %0 = load i32, i32* %arrayidx, align 2
+  %.off = add i32 %0, 9
+  %1 = icmp ult i32 %.off, 19
+  br i1 %1, label %if.then, label %for.inc
+
+if.then:                                          ; preds = %for.body
+  store i32 0, i32* %arrayidx, align 2
+  br label %for.inc
+
+for.inc:                                          ; preds = %for.body, %if.then
+  %inc = add nuw nsw i32 %i.013, 1
+  %exitcond = icmp eq i32 %inc, %n
+  br i1 %exitcond, label %for.cond.cleanup.loopexit, label %for.body
+
+for.cond.cleanup.loopexit:                        ; preds = %for.inc
+  br label %for.cond.cleanup
+
+for.cond.cleanup:                                 ; preds = %for.cond.cleanup.loopexit, %entry
+  ret void
+}
+
+; CHECK-LABEL: test_i32_noalign
+; CHECK: call void @llvm.masked.store.v4i32.p0v4i32
+define void @test_i32_noalign(i32* nocapture %A, i32 %n) #0 {
+entry:
+  %cmp12 = icmp sgt i32 %n, 0
+  br i1 %cmp12, label %for.body.preheader, label %for.cond.cleanup
+
+for.body.preheader:                               ; preds = %entry
+  br label %for.body
+
+for.body:                                         ; preds = %for.body.preheader, %for.inc
+  %i.013 = phi i32 [ %inc, %for.inc ], [ 0, %for.body.preheader ]
+  %arrayidx = getelementptr inbounds i32, i32* %A, i32 %i.013
+  %0 = load i32, i32* %arrayidx
+  %.off = add i32 %0, 9
+  %1 = icmp ult i32 %.off, 19
+  br i1 %1, label %if.then, label %for.inc
+
+if.then:                                          ; preds = %for.body
+  store i32 0, i32* %arrayidx
+  br label %for.inc
+
+for.inc:                                          ; preds = %for.body, %if.then
+  %inc = add nuw nsw i32 %i.013, 1
+  %exitcond = icmp eq i32 %inc, %n
+  br i1 %exitcond, label %for.cond.cleanup.loopexit, label %for.body
+
+for.cond.cleanup.loopexit:                        ; preds = %for.inc
+  br label %for.cond.cleanup
+
+for.cond.cleanup:                                 ; preds = %for.cond.cleanup.loopexit, %entry
+  ret void
+}
+
+; CHECK-LABEL: test_i16_align2
+; CHECK: call void @llvm.masked.store.v8i16.p0v8i16
+define void @test_i16_align2(i16* nocapture %A, i32 %n) #0 {
+entry:
+  %cmp12 = icmp sgt i32 %n, 0
+  br i1 %cmp12, label %for.body.preheader, label %for.cond.cleanup
+
+for.body.preheader:                               ; preds = %entry
+  br label %for.body
+
+for.body:                                         ; preds = %for.body.preheader, %for.inc
+  %i.013 = phi i32 [ %inc, %for.inc ], [ 0, %for.body.preheader ]
+  %arrayidx = getelementptr inbounds i16, i16* %A, i32 %i.013
+  %0 = load i16, i16* %arrayidx, align 2
+  %.off = add i16 %0, 9
+  %1 = icmp ult i16 %.off, 19
+  br i1 %1, label %if.then, label %for.inc
+
+if.then:                                          ; preds = %for.body
+  store i16 0, i16* %arrayidx, align 2
+  br label %for.inc
+
+for.inc:                                          ; preds = %for.body, %if.then
+  %inc = add nuw nsw i32 %i.013, 1
+  %exitcond = icmp eq i32 %inc, %n
+  br i1 %exitcond, label %for.cond.cleanup.loopexit, label %for.body
+
+for.cond.cleanup.loopexit:                        ; preds = %for.inc
+  br label %for.cond.cleanup
+
+for.cond.cleanup:                                 ; preds = %for.cond.cleanup.loopexit, %entry
+  ret void
+}
+
+; CHECK-LABEL: test_i16_align1
+; CHECK-NOT: call void @llvm.masked.store
+define void @test_i16_align1(i16* nocapture %A, i32 %n) #0 {
+entry:
+  %cmp12 = icmp sgt i32 %n, 0
+  br i1 %cmp12, label %for.body.preheader, label %for.cond.cleanup
+
+for.body.preheader:                               ; preds = %entry
+  br label %for.body
+
+for.body:                                         ; preds = %for.body.preheader, %for.inc
+  %i.013 = phi i32 [ %inc, %for.inc ], [ 0, %for.body.preheader ]
+  %arrayidx = getelementptr inbounds i16, i16* %A, i32 %i.013
+  %0 = load i16, i16* %arrayidx, align 1
+  %.off = add i16 %0, 9
+  %1 = icmp ult i16 %.off, 19
+  br i1 %1, label %if.then, label %for.inc
+
+if.then:                                          ; preds = %for.body
+  store i16 0, i16* %arrayidx, align 1
+  br label %for.inc
+
+for.inc:                                          ; preds = %for.body, %if.then
+  %inc = add nuw nsw i32 %i.013, 1
+  %exitcond = icmp eq i32 %inc, %n
+  br i1 %exitcond, label %for.cond.cleanup.loopexit, label %for.body
+
+for.cond.cleanup.loopexit:                        ; preds = %for.inc
+  br label %for.cond.cleanup
+
+for.cond.cleanup:                                 ; preds = %for.cond.cleanup.loopexit, %entry
+  ret void
+}
+
 attributes #0 = { "target-features"="+mve" }