(i64 (zext (srl GR32 8))) -> movzbl AH is not safe since srl 8 only clear the top...

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72618 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/X86/X86Instr64bit.td b/lib/Target/X86/X86Instr64bit.td
index f58ba8db2b8686eb8076521cb6beea975660f849..0babaa46f2d9883682fb41cb685ca1e2d548e80f 100644 (file)
--- a/lib/Target/X86/X86Instr64bit.td
+++ b/lib/Target/X86/X86Instr64bit.td
@@ -1607,13 +1607,6 @@ def : Pat<(and (srl_su GR32:$src, (i8 8)), (i32 255)),
             (EXTRACT_SUBREG (COPY_TO_REGCLASS GR32:$src, GR32_ABCD),
                             x86_subreg_8bit_hi))>,
       Requires<[In64BitMode]>;
-def : Pat<(i64 (zext (srl_su GR32:$src, (i8 8)))),
-          (SUBREG_TO_REG
-            (i64 0),
-            (MOVZX32_NOREXrr8
-              (EXTRACT_SUBREG (COPY_TO_REGCLASS GR32:$src, GR32_ABCD),
-                              x86_subreg_8bit_hi)),
-            x86_subreg_32bit)>;
 def : Pat<(srl_su GR16:$src, (i8 8)),
           (EXTRACT_SUBREG
             (MOVZX32_NOREXrr8

diff --git a/test/CodeGen/X86/2009-05-30-ISelBug.ll b/test/CodeGen/X86/2009-05-30-ISelBug.ll
new file mode 100644 (file)
index 0000000..373f91f
--- /dev/null
+++ b/test/CodeGen/X86/2009-05-30-ISelBug.ll
@@ -0,0 +1,28 @@
+; RUN: llvm-as < %s | llc -march=x86-64 | not grep {movzbl     %\[abcd\]h,}
+
+define void @BZ2_bzDecompress_bb5_2E_outer_bb35_2E_i_bb54_2E_i(i32*, i32 %c_nblock_used.2.i, i32 %.reload51, i32* %.out, i32* %.out1, i32* %.out2, i32* %.out3) nounwind {
+newFuncRoot:
+       br label %bb54.i
+
+bb35.i.backedge.exitStub:              ; preds = %bb54.i
+       store i32 %6, i32* %.out
+       store i32 %10, i32* %.out1
+       store i32 %11, i32* %.out2
+       store i32 %12, i32* %.out3
+       ret void
+
+bb54.i:                ; preds = %newFuncRoot
+       %1 = zext i32 %.reload51 to i64         ; <i64> [#uses=1]
+       %2 = getelementptr i32* %0, i64 %1              ; <i32*> [#uses=1]
+       %3 = load i32* %2, align 4              ; <i32> [#uses=2]
+       %4 = lshr i32 %3, 8             ; <i32> [#uses=1]
+       %5 = and i32 %3, 255            ; <i32> [#uses=1]
+       %6 = add i32 %5, 4              ; <i32> [#uses=1]
+       %7 = zext i32 %4 to i64         ; <i64> [#uses=1]
+       %8 = getelementptr i32* %0, i64 %7              ; <i32*> [#uses=1]
+       %9 = load i32* %8, align 4              ; <i32> [#uses=2]
+       %10 = and i32 %9, 255           ; <i32> [#uses=1]
+       %11 = lshr i32 %9, 8            ; <i32> [#uses=1]
+       %12 = add i32 %c_nblock_used.2.i, 5             ; <i32> [#uses=1]
+       br label %bb35.i.backedge.exitStub
+}