instcombine: Migrate toascii optimizations

This patch migrates the toascii optimizations from the simplify-libcalls
pass into the instcombine library call simplifier.

llvm-svn: 168580

1 files changed, 59 insertions, 0 deletions

diff --git a/llvm/test/Transforms/InstCombine/toascii-1.ll b/llvm/test/Transforms/InstCombine/toascii-1.ll
new file mode 100644
index 00000000000..c4a13e22939
--- /dev/null
+++ b/llvm/test/Transforms/InstCombine/toascii-1.ll
@@ -0,0 +1,59 @@
+; Test that the toascii library call simplifier works correctly.
+;
+; RUN: opt < %s -instcombine -S | FileCheck %s
+
+target datalayout = "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-a0:0:64-f80:128:128"
+
+declare i32 @toascii(i32)
+
+; Check isascii(c) -> c & 0x7f.
+
+define i32 @test_simplify1() {
+; CHECK: @test_simplify1
+  %ret = call i32 @toascii(i32 0)
+  ret i32 %ret
+; CHECK-NEXT: ret i32 0
+}
+
+define i32 @test_simplify2() {
+; CHECK: @test_simplify2
+  %ret = call i32 @toascii(i32 1)
+  ret i32 %ret
+; CHECK-NEXT: ret i32 1
+}
+
+define i32 @test_simplify3() {
+; CHECK: @test_simplify3
+  %ret = call i32 @toascii(i32 127)
+  ret i32 %ret
+; CHECK-NEXT: ret i32 127
+}
+
+define i32 @test_simplify4() {
+; CHECK: @test_simplify4
+  %ret = call i32 @toascii(i32 128)
+  ret i32 %ret
+; CHECK-NEXT: ret i32 0
+}
+
+define i32 @test_simplify5() {
+; CHECK: @test_simplify5
+  %ret = call i32 @toascii(i32 255)
+  ret i32 %ret
+; CHECK-NEXT: ret i32 127
+}
+
+define i32 @test_simplify6() {
+; CHECK: @test_simplify6
+  %ret = call i32 @toascii(i32 256)
+  ret i32 %ret
+; CHECK-NEXT: ret i32 0
+}
+
+define i32 @test_simplify7(i32 %x) {
+; CHECK: @test_simplify7
+  %ret = call i32 @toascii(i32 %x)
+; CHECK-NEXT: [[AND:%[a-z0-9]+]] = and i32 %x, 127
+  ret i32 %ret
+; CHECK-NEXT: ret i32 [[AND]]
+}