Another revsh pattern. rdar://9609059

llvm-svn: 133064

llvm/lib/Target/ARM/ARMInstrInfo.td

@@ -3029,6 +3029,10 @@ def : ARMV6Pat<(sext_inreg (or (srl (and GPR:$Rm, 0xFF00), (i32 8)),
                                (shl GPR:$Rm, (i32 8))), i16),
                (REVSH GPR:$Rm)>;
 
+def : ARMV6Pat<(or (sra (shl GPR:$Rm, (i32 24)), (i32 16)),
+                   (and (srl GPR:$Rm, (i32 8)), 0xFF)),
+               (REVSH GPR:$Rm)>;
+
 // Need the AddedComplexity or else MOVs + REV would be chosen.
 let AddedComplexity = 5 in
 def : ARMV6Pat<(sra (bswap GPR:$Rm), (i32 16)), (REVSH GPR:$Rm)>;

llvm/lib/Target/ARM/ARMInstrThumb2.td

@@ -2604,6 +2604,10 @@ def : T2Pat<(sext_inreg (or (srl (and rGPR:$Rm, 0xFF00), (i32 8)),
                             (shl rGPR:$Rm, (i32 8))), i16),
             (t2REVSH rGPR:$Rm)>;
 
+def : T2Pat<(or (sra (shl rGPR:$Rm, (i32 24)), (i32 16)),
+                   (and (srl rGPR:$Rm, (i32 8)), 0xFF)),
+            (t2REVSH rGPR:$Rm)>;
+
 def : T2Pat<(sra (bswap rGPR:$Rm), (i32 16)), (t2REVSH rGPR:$Rm)>;
 
 def t2PKHBT : T2ThreeReg<

llvm/test/CodeGen/ARM/rev.ll

@@ -54,3 +54,16 @@ entry:
   %conv8 = ashr exact i32 %sext, 16
   ret i32 %conv8
 }
+
+; rdar://9609059
+define i32 @test5(i32 %i) nounwind readnone {
+entry:
+; CHECK: test5
+; CHECK: revsh r0, r0
+  %shl = shl i32 %i, 24
+  %shr = ashr exact i32 %shl, 16
+  %shr23 = lshr i32 %i, 8
+  %and = and i32 %shr23, 255
+  %or = or i32 %shr, %and
+  ret i32 %or
+}