[SystemZ] Utilize Test Data Class instructions.

This adds a new SystemZ-specific intrinsic, llvm.s390.tdc.f(32|64|128),
which maps straight to the test data class instructions.  A new IR pass
is added to recognize instructions that can be converted to TDC and
perform the necessary replacements.

Differential Revision: http://reviews.llvm.org/D21949

llvm-svn: 275016

1 files changed, 85 insertions, 0 deletions

diff --git a/llvm/test/CodeGen/SystemZ/tdc-04.ll b/llvm/test/CodeGen/SystemZ/tdc-04.ll
new file mode 100644
index 00000000000..929285b0ba8
--- /dev/null
+++ b/llvm/test/CodeGen/SystemZ/tdc-04.ll
@@ -0,0 +1,85 @@
+; Test the Test Data Class instruction logic operation conversion from
+; signbit extraction.
+;
+; RUN: llc < %s -mtriple=s390x-linux-gnu | FileCheck %s
+;
+
+; Extract sign bit.
+define i32 @f1(float %x) {
+; CHECK-LABEL: f1
+; CHECK: tceb %f0, 1365
+  %cast = bitcast float %x to i32
+  %res = icmp slt i32 %cast, 0
+  %xres = zext i1 %res to i32
+  ret i32 %xres
+}
+
+; Extract negated sign bit.
+define i32 @f2(float %x) {
+; CHECK-LABEL: f2
+; CHECK: tceb %f0, 2730
+  %cast = bitcast float %x to i32
+  %res = icmp sgt i32 %cast, -1
+  %xres = zext i1 %res to i32
+  ret i32 %xres
+}
+
+; Extract sign bit.
+define i32 @f3(double %x) {
+; CHECK-LABEL: f3
+; CHECK: tcdb %f0, 1365
+  %cast = bitcast double %x to i64
+  %res = icmp slt i64 %cast, 0
+  %xres = zext i1 %res to i32
+  ret i32 %xres
+}
+
+; Extract negated sign bit.
+define i32 @f4(double %x) {
+; CHECK-LABEL: f4
+; CHECK: tcdb %f0, 2730
+  %cast = bitcast double %x to i64
+  %res = icmp sgt i64 %cast, -1
+  %xres = zext i1 %res to i32
+  ret i32 %xres
+}
+
+; Extract sign bit.
+define i32 @f5(fp128 %x) {
+; CHECK-LABEL: f5
+; CHECK: tcxb %f0, 1365
+  %cast = bitcast fp128 %x to i128
+  %res = icmp slt i128 %cast, 0
+  %xres = zext i1 %res to i32
+  ret i32 %xres
+}
+
+; Extract negated sign bit.
+define i32 @f6(fp128 %x) {
+; CHECK-LABEL: f6
+; CHECK: tcxb %f0, 2730
+  %cast = bitcast fp128 %x to i128
+  %res = icmp sgt i128 %cast, -1
+  %xres = zext i1 %res to i32
+  ret i32 %xres
+}
+
+; Wrong const.
+define i32 @f7(float %x) {
+; CHECK-LABEL: f7
+; CHECK-NOT: tceb
+  %cast = bitcast float %x to i32
+  %res = icmp slt i32 %cast, -1
+  %xres = zext i1 %res to i32
+  ret i32 %xres
+}
+
+; Wrong pred.
+define i32 @f8(float %x) {
+; CHECK-LABEL: f8
+; CHECK-NOT: tceb
+  %cast = bitcast float %x to i32
+  %res = icmp eq i32 %cast, 0
+  %xres = zext i1 %res to i32
+  ret i32 %xres
+}