If it's determined safe, remat MOV32r0 (i.e. xor r, r) and others as it is instead of using the longer MOV32ri instruction.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52670 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 45 insertions, 0 deletions

diff --git a/test/CodeGen/X86/remat-mov0.ll b/test/CodeGen/X86/remat-mov0.ll
new file mode 100644
index 0000000000..ea39c7bc73
--- /dev/null
+++ b/test/CodeGen/X86/remat-mov0.ll
@@ -0,0 +1,45 @@
+; RUN: llvm-as < %s | llc -march=x86 | grep xor | count 3
+
+	%struct.FILE = type { i8*, i32, i32, i16, i16, %struct.__sbuf, i32, i8*, i32 (i8*)*, i32 (i8*, i8*, i32)*, i64 (i8*, i64, i32)*, i32 (i8*, i8*, i32)*, %struct.__sbuf, %struct.__sFILEX*, i32, [3 x i8], [1 x i8], %struct.__sbuf, i32, i64 }
+	%struct.ImgT = type { i8, i8*, i8*, %struct.FILE*, i32, i32, i32, i32, i8*, double*, float*, float*, float*, i32*, double, double, i32*, double*, i32*, i32* }
+	%struct._CompT = type { i32, i32, i32, i32, i32, i32, i32, i32, i32, float, float, i8, %struct._PixT*, %struct._CompT*, i8, %struct._CompT* }
+	%struct._PixT = type { i32, i32, %struct._PixT* }
+	%struct.__sFILEX = type opaque
+	%struct.__sbuf = type { i8*, i32 }
+
+declare fastcc void @MergeComponents(%struct._CompT*, %struct._CompT*, %struct._CompT*, %struct._CompT**, %struct.ImgT*) nounwind 
+
+define fastcc void @MergeToLeft(%struct._CompT* %comp, %struct._CompT** %head, %struct.ImgT* %img) nounwind  {
+entry:
+	br label %bb208
+
+bb105:		; preds = %bb200
+	br i1 false, label %bb197, label %bb149
+
+bb149:		; preds = %bb105
+	%tmp151 = getelementptr %struct._CompT* null, i32 0, i32 0		; <i32*> [#uses=1]
+	br i1 false, label %bb184, label %bb193
+
+bb184:		; preds = %bb149
+	tail call fastcc void @MergeComponents( %struct._CompT* %comp, %struct._CompT* null, %struct._CompT* null, %struct._CompT** %head, %struct.ImgT* %img ) nounwind 
+	tail call fastcc void @MergeToLeft( %struct._CompT* %comp, %struct._CompT** %head, %struct.ImgT* %img ) nounwind 
+	br label %bb193
+
+bb193:		; preds = %bb184, %bb149
+	%tmp196 = load i32* %tmp151, align 4		; <i32> [#uses=1]
+	br label %bb197
+
+bb197:		; preds = %bb193, %bb105
+	%last_comp.0 = phi i32 [ %tmp196, %bb193 ], [ 0, %bb105 ]		; <i32> [#uses=0]
+	%indvar.next = add i32 %indvar, 1		; <i32> [#uses=1]
+	br label %bb200
+
+bb200:		; preds = %bb208, %bb197
+	%indvar = phi i32 [ 0, %bb208 ], [ %indvar.next, %bb197 ]		; <i32> [#uses=2]
+	%xm.0 = sub i32 %indvar, 0		; <i32> [#uses=1]
+	%tmp202 = icmp slt i32 %xm.0, 1		; <i1> [#uses=1]
+	br i1 %tmp202, label %bb105, label %bb208
+
+bb208:		; preds = %bb200, %entry
+	br label %bb200
+}