Spiller may unfold load / mod / store instructions as an optimization when the would be loaded value is available in a register. It needs to check if it's legal to clobber the register. Also, the register can contain values of multiple spill slots, make sure to check all instead of just the one being unfolded.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@67068 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 167 insertions, 0 deletions

diff --git a/test/CodeGen/X86/2009-03-16-SpillerBug.ll b/test/CodeGen/X86/2009-03-16-SpillerBug.ll
new file mode 100644
index 0000000000..e633d35098
--- /dev/null
+++ b/test/CodeGen/X86/2009-03-16-SpillerBug.ll
@@ -0,0 +1,167 @@
+; RUN: llvm-as < %s | llc -mtriple=i386-apple-darwin -stats |& grep spiller | not grep {stores unfolded}
+; rdar://6682365
+
+; Do not clobber a register if another spill slot is available in it and it's marked "do not clobber".
+
+	%struct.CAST_KEY = type { [32 x i32], i32 }
+@CAST_S_table0 = constant [2 x i32] [i32 821772500, i32 -1616838901], align 32		; <[2 x i32]*> [#uses=0]
+@CAST_S_table4 = constant [2 x i32] [i32 2127105028, i32 745436345], align 32		; <[2 x i32]*> [#uses=6]
+@CAST_S_table5 = constant [2 x i32] [i32 -151351395, i32 749497569], align 32		; <[2 x i32]*> [#uses=5]
+@CAST_S_table6 = constant [2 x i32] [i32 -2048901095, i32 858518887], align 32		; <[2 x i32]*> [#uses=4]
+@CAST_S_table7 = constant [2 x i32] [i32 -501862387, i32 -1143078916], align 32		; <[2 x i32]*> [#uses=5]
+@CAST_S_table1 = constant [2 x i32] [i32 522195092, i32 -284448933], align 32		; <[2 x i32]*> [#uses=0]
+@CAST_S_table2 = constant [2 x i32] [i32 -1913667008, i32 637164959], align 32		; <[2 x i32]*> [#uses=0]
+@CAST_S_table3 = constant [2 x i32] [i32 -1649212384, i32 532081118], align 32		; <[2 x i32]*> [#uses=0]
+
+define void @CAST_set_key(%struct.CAST_KEY* nocapture %key, i32 %len, i8* nocapture %data) nounwind ssp {
+bb1.thread:
+	%0 = getelementptr [16 x i32]* null, i32 0, i32 5		; <i32*> [#uses=1]
+	%1 = getelementptr [16 x i32]* null, i32 0, i32 8		; <i32*> [#uses=1]
+	%2 = load i32* null, align 4		; <i32> [#uses=1]
+	%3 = shl i32 %2, 24		; <i32> [#uses=1]
+	%4 = load i32* null, align 4		; <i32> [#uses=1]
+	%5 = shl i32 %4, 16		; <i32> [#uses=1]
+	%6 = load i32* null, align 4		; <i32> [#uses=1]
+	%7 = or i32 %5, %3		; <i32> [#uses=1]
+	%8 = or i32 %7, %6		; <i32> [#uses=1]
+	%9 = or i32 %8, 0		; <i32> [#uses=1]
+	%10 = load i32* null, align 4		; <i32> [#uses=1]
+	%11 = shl i32 %10, 24		; <i32> [#uses=1]
+	%12 = load i32* %0, align 4		; <i32> [#uses=1]
+	%13 = shl i32 %12, 16		; <i32> [#uses=1]
+	%14 = load i32* null, align 4		; <i32> [#uses=1]
+	%15 = or i32 %13, %11		; <i32> [#uses=1]
+	%16 = or i32 %15, %14		; <i32> [#uses=1]
+	%17 = or i32 %16, 0		; <i32> [#uses=1]
+	br label %bb11
+
+bb11:		; preds = %bb11, %bb1.thread
+	%18 = phi i32 [ %110, %bb11 ], [ 0, %bb1.thread ]		; <i32> [#uses=1]
+	%19 = phi i32 [ %112, %bb11 ], [ 0, %bb1.thread ]		; <i32> [#uses=0]
+	%20 = phi i32 [ 0, %bb11 ], [ 0, %bb1.thread ]		; <i32> [#uses=0]
+	%21 = phi i32 [ %113, %bb11 ], [ 0, %bb1.thread ]		; <i32> [#uses=1]
+	%X.0.0 = phi i32 [ %9, %bb1.thread ], [ %92, %bb11 ]		; <i32> [#uses=0]
+	%X.1.0 = phi i32 [ %17, %bb1.thread ], [ 0, %bb11 ]		; <i32> [#uses=0]
+	%22 = getelementptr [2 x i32]* @CAST_S_table6, i32 0, i32 %21		; <i32*> [#uses=0]
+	%23 = getelementptr [2 x i32]* @CAST_S_table5, i32 0, i32 %18		; <i32*> [#uses=0]
+	%24 = load i32* null, align 4		; <i32> [#uses=1]
+	%25 = xor i32 0, %24		; <i32> [#uses=1]
+	%26 = xor i32 %25, 0		; <i32> [#uses=1]
+	%27 = xor i32 %26, 0		; <i32> [#uses=4]
+	%28 = and i32 %27, 255		; <i32> [#uses=2]
+	%29 = lshr i32 %27, 8		; <i32> [#uses=1]
+	%30 = and i32 %29, 255		; <i32> [#uses=2]
+	%31 = lshr i32 %27, 16		; <i32> [#uses=1]
+	%32 = and i32 %31, 255		; <i32> [#uses=1]
+	%33 = getelementptr [2 x i32]* @CAST_S_table4, i32 0, i32 %28		; <i32*> [#uses=1]
+	%34 = load i32* %33, align 4		; <i32> [#uses=2]
+	%35 = getelementptr [2 x i32]* @CAST_S_table5, i32 0, i32 %30		; <i32*> [#uses=1]
+	%36 = load i32* %35, align 4		; <i32> [#uses=2]
+	%37 = xor i32 %34, 0		; <i32> [#uses=1]
+	%38 = xor i32 %37, %36		; <i32> [#uses=1]
+	%39 = xor i32 %38, 0		; <i32> [#uses=1]
+	%40 = xor i32 %39, 0		; <i32> [#uses=1]
+	%41 = xor i32 %40, 0		; <i32> [#uses=3]
+	%42 = lshr i32 %41, 8		; <i32> [#uses=1]
+	%43 = and i32 %42, 255		; <i32> [#uses=2]
+	%44 = lshr i32 %41, 16		; <i32> [#uses=1]
+	%45 = and i32 %44, 255		; <i32> [#uses=1]
+	%46 = getelementptr [2 x i32]* @CAST_S_table4, i32 0, i32 %43		; <i32*> [#uses=1]
+	%47 = load i32* %46, align 4		; <i32> [#uses=1]
+	%48 = load i32* null, align 4		; <i32> [#uses=1]
+	%49 = xor i32 %47, 0		; <i32> [#uses=1]
+	%50 = xor i32 %49, %48		; <i32> [#uses=1]
+	%51 = xor i32 %50, 0		; <i32> [#uses=1]
+	%52 = xor i32 %51, 0		; <i32> [#uses=1]
+	%53 = xor i32 %52, 0		; <i32> [#uses=2]
+	%54 = and i32 %53, 255		; <i32> [#uses=1]
+	%55 = lshr i32 %53, 24		; <i32> [#uses=1]
+	%56 = getelementptr [2 x i32]* @CAST_S_table6, i32 0, i32 %55		; <i32*> [#uses=1]
+	%57 = load i32* %56, align 4		; <i32> [#uses=1]
+	%58 = xor i32 0, %57		; <i32> [#uses=1]
+	%59 = xor i32 %58, 0		; <i32> [#uses=1]
+	%60 = xor i32 %59, 0		; <i32> [#uses=1]
+	store i32 %60, i32* null, align 4
+	%61 = getelementptr [2 x i32]* @CAST_S_table4, i32 0, i32 0		; <i32*> [#uses=1]
+	%62 = load i32* %61, align 4		; <i32> [#uses=1]
+	%63 = getelementptr [2 x i32]* @CAST_S_table7, i32 0, i32 %54		; <i32*> [#uses=1]
+	%64 = load i32* %63, align 4		; <i32> [#uses=1]
+	%65 = xor i32 0, %64		; <i32> [#uses=1]
+	%66 = xor i32 %65, 0		; <i32> [#uses=1]
+	store i32 %66, i32* null, align 4
+	%67 = getelementptr [2 x i32]* @CAST_S_table7, i32 0, i32 %45		; <i32*> [#uses=1]
+	%68 = load i32* %67, align 4		; <i32> [#uses=1]
+	%69 = xor i32 %36, %34		; <i32> [#uses=1]
+	%70 = xor i32 %69, 0		; <i32> [#uses=1]
+	%71 = xor i32 %70, %68		; <i32> [#uses=1]
+	%72 = xor i32 %71, 0		; <i32> [#uses=1]
+	store i32 %72, i32* null, align 4
+	%73 = getelementptr [2 x i32]* @CAST_S_table4, i32 0, i32 %32		; <i32*> [#uses=1]
+	%74 = load i32* %73, align 4		; <i32> [#uses=2]
+	%75 = load i32* null, align 4		; <i32> [#uses=1]
+	%76 = getelementptr [2 x i32]* @CAST_S_table6, i32 0, i32 %43		; <i32*> [#uses=1]
+	%77 = load i32* %76, align 4		; <i32> [#uses=1]
+	%78 = getelementptr [2 x i32]* @CAST_S_table7, i32 0, i32 0		; <i32*> [#uses=1]
+	%79 = load i32* %78, align 4		; <i32> [#uses=1]
+	%80 = getelementptr [2 x i32]* @CAST_S_table7, i32 0, i32 %30		; <i32*> [#uses=1]
+	%81 = load i32* %80, align 4		; <i32> [#uses=2]
+	%82 = xor i32 %75, %74		; <i32> [#uses=1]
+	%83 = xor i32 %82, %77		; <i32> [#uses=1]
+	%84 = xor i32 %83, %79		; <i32> [#uses=1]
+	%85 = xor i32 %84, %81		; <i32> [#uses=1]
+	store i32 %85, i32* null, align 4
+	%86 = getelementptr [2 x i32]* @CAST_S_table5, i32 0, i32 %28		; <i32*> [#uses=1]
+	%87 = load i32* %86, align 4		; <i32> [#uses=1]
+	%88 = xor i32 %74, %41		; <i32> [#uses=1]
+	%89 = xor i32 %88, %87		; <i32> [#uses=1]
+	%90 = xor i32 %89, 0		; <i32> [#uses=1]
+	%91 = xor i32 %90, %81		; <i32> [#uses=1]
+	%92 = xor i32 %91, 0		; <i32> [#uses=3]
+	%93 = lshr i32 %92, 16		; <i32> [#uses=1]
+	%94 = and i32 %93, 255		; <i32> [#uses=1]
+	store i32 %94, i32* null, align 4
+	%95 = lshr i32 %92, 24		; <i32> [#uses=2]
+	%96 = getelementptr [2 x i32]* @CAST_S_table4, i32 0, i32 %95		; <i32*> [#uses=1]
+	%97 = load i32* %96, align 4		; <i32> [#uses=1]
+	%98 = getelementptr [2 x i32]* @CAST_S_table5, i32 0, i32 0		; <i32*> [#uses=1]
+	%99 = load i32* %98, align 4		; <i32> [#uses=1]
+	%100 = load i32* null, align 4		; <i32> [#uses=0]
+	%101 = xor i32 %97, 0		; <i32> [#uses=1]
+	%102 = xor i32 %101, %99		; <i32> [#uses=1]
+	%103 = xor i32 %102, 0		; <i32> [#uses=1]
+	%104 = xor i32 %103, 0		; <i32> [#uses=0]
+	store i32 0, i32* null, align 4
+	%105 = xor i32 0, %27		; <i32> [#uses=1]
+	%106 = xor i32 %105, 0		; <i32> [#uses=1]
+	%107 = xor i32 %106, 0		; <i32> [#uses=1]
+	%108 = xor i32 %107, 0		; <i32> [#uses=1]
+	%109 = xor i32 %108, %62		; <i32> [#uses=3]
+	%110 = and i32 %109, 255		; <i32> [#uses=1]
+	%111 = lshr i32 %109, 16		; <i32> [#uses=1]
+	%112 = and i32 %111, 255		; <i32> [#uses=1]
+	%113 = lshr i32 %109, 24		; <i32> [#uses=3]
+	store i32 %113, i32* %1, align 4
+	%114 = load i32* null, align 4		; <i32> [#uses=1]
+	%115 = xor i32 0, %114		; <i32> [#uses=1]
+	%116 = xor i32 %115, 0		; <i32> [#uses=1]
+	%117 = xor i32 %116, 0		; <i32> [#uses=1]
+	%K.0.sum42 = or i32 0, 12		; <i32> [#uses=1]
+	%118 = getelementptr [32 x i32]* null, i32 0, i32 %K.0.sum42		; <i32*> [#uses=1]
+	store i32 %117, i32* %118, align 4
+	%119 = getelementptr [2 x i32]* @CAST_S_table5, i32 0, i32 0		; <i32*> [#uses=0]
+	store i32 0, i32* null, align 4
+	%120 = getelementptr [2 x i32]* @CAST_S_table6, i32 0, i32 %113		; <i32*> [#uses=1]
+	%121 = load i32* %120, align 4		; <i32> [#uses=1]
+	%122 = xor i32 0, %121		; <i32> [#uses=1]
+	store i32 %122, i32* null, align 4
+	%123 = getelementptr [2 x i32]* @CAST_S_table4, i32 0, i32 0		; <i32*> [#uses=1]
+	%124 = load i32* %123, align 4		; <i32> [#uses=1]
+	%125 = getelementptr [2 x i32]* @CAST_S_table7, i32 0, i32 %95		; <i32*> [#uses=1]
+	%126 = load i32* %125, align 4		; <i32> [#uses=1]
+	%127 = xor i32 0, %124		; <i32> [#uses=1]
+	%128 = xor i32 %127, 0		; <i32> [#uses=1]
+	%129 = xor i32 %128, %126		; <i32> [#uses=1]
+	%130 = xor i32 %129, 0		; <i32> [#uses=1]
+	store i32 %130, i32* null, align 4
+	br label %bb11
+}