[CodeGenPrepare] Move Extension Instructions Through Logical And Shift Instructions

CodeGenPrepare pass move extension instructions close to load instructions in different BB, so they can be combined later. But the extension instructions can't move through logical and shift instructions in current implementation. This patch enables this enhancement, so we can eliminate more extension instructions.

Differential Revision: https://reviews.llvm.org/D45537

llvm-svn: 331783

1 files changed, 128 insertions, 0 deletions

diff --git a/llvm/test/Transforms/CodeGenPrepare/X86/ext-logicop.ll b/llvm/test/Transforms/CodeGenPrepare/X86/ext-logicop.ll
new file mode 100644
index 00000000000..51d1e0ab676
--- /dev/null
+++ b/llvm/test/Transforms/CodeGenPrepare/X86/ext-logicop.ll
@@ -0,0 +1,128 @@
+; RUN: opt < %s -codegenprepare -S -mtriple=x86_64-unknown-unknown    | FileCheck %s
+
+
+@a = global [10 x i8] zeroinitializer, align 1
+declare void @foo()
+
+; ext(and(ld, cst)) -> and(ext(ld), ext(cst))
+define void @test1(i32* %p, i32 %ll) {
+; CHECK-LABEL: @test1
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    load
+; CHECK-NEXT:    zext
+; CHECK-NEXT:    and
+entry:
+  %tmp = load i8, i8* getelementptr inbounds ([10 x i8], [10 x i8]* @a, i64 0, i64 0), align 1
+  %and = and i8 %tmp, 60
+  %cmp = icmp ugt i8 %and, 20
+  br i1 %cmp, label %if.then, label %if.end
+
+if.then:                                          ; preds = %entry
+  %conv2 = zext i8 %and to i32
+  %add = add nsw i32 %conv2, %ll
+  store i32 %add, i32* %p, align 4
+  br label %if.end
+
+if.end:                                           ; preds = %if.then, %entry
+  tail call void @foo()
+  ret void
+}
+
+; ext(or(ld, cst)) -> or(ext(ld), ext(cst))
+define void @test2(i32* %p, i32 %ll) {
+; CHECK-LABEL: @test2
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    load
+; CHECK-NEXT:    zext
+; CHECK-NEXT:    or
+entry:
+  %tmp = load i8, i8* getelementptr inbounds ([10 x i8], [10 x i8]* @a, i64 0, i64 0), align 1
+  %or = or i8 %tmp, 60
+  %cmp = icmp ugt i8 %or, 20
+  br i1 %cmp, label %if.then, label %if.end
+
+if.then:                                          ; preds = %entry
+  %conv2 = zext i8 %or to i32
+  %add = add nsw i32 %conv2, %ll
+  store i32 %add, i32* %p, align 4
+  br label %if.end
+
+if.end:                                           ; preds = %if.then, %entry
+  tail call void @foo()
+  ret void
+}
+
+; ext(and(shl(ld, cst), cst)) -> and(shl(ext(ld), ext(cst)), ext(cst))
+define void @test3(i32* %p, i32 %ll) {
+; CHECK-LABEL: @test3
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    load
+; CHECK-NEXT:    zext
+; CHECK-NEXT:    shl
+; CHECK-NEXT:    and
+entry:
+  %tmp = load i8, i8* getelementptr inbounds ([10 x i8], [10 x i8]* @a, i64 0, i64 0), align 1
+  %shl = shl i8 %tmp, 2
+  %and = and i8 %shl, 60
+  %cmp = icmp ugt i8 %and, 20
+  br i1 %cmp, label %if.then, label %if.end
+
+if.then:                                          ; preds = %entry
+  %conv2 = zext i8 %and to i32
+  %add = add nsw i32 %conv2, %ll
+  store i32 %add, i32* %p, align 4
+  br label %if.end
+
+if.end:                                           ; preds = %if.then, %entry
+  tail call void @foo()
+  ret void
+}
+
+; zext(shrl(ld, cst)) -> shrl(zext(ld), zext(cst))
+define void @test4(i32* %p, i32 %ll) {
+; CHECK-LABEL: @test4
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    load
+; CHECK-NEXT:    zext
+; CHECK-NEXT:    lshr
+entry:
+  %tmp = load i8, i8* getelementptr inbounds ([10 x i8], [10 x i8]* @a, i64 0, i64 0), align 1
+  %lshr = lshr i8 %tmp, 2
+  %cmp = icmp ugt i8 %lshr, 20
+  br i1 %cmp, label %if.then, label %if.end
+
+if.then:                                          ; preds = %entry
+  %conv2 = zext i8 %lshr to i32
+  %add = add nsw i32 %conv2, %ll
+  store i32 %add, i32* %p, align 4
+  br label %if.end
+
+if.end:                                           ; preds = %if.then, %entry
+  tail call void @foo()
+  ret void
+}
+
+; ext(xor(ld, cst)) -> xor(ext(ld), ext(cst))
+define void @test5(i32* %p, i32 %ll) {
+; CHECK-LABEL: @test5
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    load
+; CHECK-NEXT:    zext
+; CHECK-NEXT:    xor
+entry:
+  %tmp = load i8, i8* getelementptr inbounds ([10 x i8], [10 x i8]* @a, i64 0, i64 0), align 1
+  %xor = xor i8 %tmp, 60
+  %cmp = icmp ugt i8 %xor, 20
+  br i1 %cmp, label %if.then, label %if.end
+
+if.then:                                          ; preds = %entry
+  %conv2 = zext i8 %xor to i32
+  %add = add nsw i32 %conv2, %ll
+  store i32 %add, i32* %p, align 4
+  br label %if.end
+
+if.end:                                           ; preds = %if.then, %entry
+  tail call void @foo()
+  ret void
+}
+