diff options
| -rw-r--r-- | llvm/lib/Target/SystemZ/SystemZInstrInfo.td | 5 | ||||
| -rw-r--r-- | llvm/test/CodeGen/SystemZ/and-xor-01.ll | 14 |
2 files changed, 19 insertions, 0 deletions
diff --git a/llvm/lib/Target/SystemZ/SystemZInstrInfo.td b/llvm/lib/Target/SystemZ/SystemZInstrInfo.td index 77a9fdd4add..7a7a3e30863 100644 --- a/llvm/lib/Target/SystemZ/SystemZInstrInfo.td +++ b/llvm/lib/Target/SystemZ/SystemZInstrInfo.td @@ -1680,6 +1680,11 @@ def : Pat<(sra (shl (i64 (anyext (i32 (z_select_ccmask 1, 0, imm32zx4:$valid, (i32 63)), (Select64 (LGHI -1), (LGHI 0), imm32zx4:$valid, imm32zx4:$cc)>; +// Avoid generating 2 XOR instructions. (xor (and x, y), y) is +// equivalent to (and (xor x, -1), y) +def : Pat<(and (xor GR64:$x, (i64 -1)), GR64:$y), + (XGR GR64:$y, (NGR GR64:$y, GR64:$x))>; + // Peepholes for turning scalar operations into block operations. defm : BlockLoadStore<anyextloadi8, i32, MVCSequence, NCSequence, OCSequence, XCSequence, 1>; diff --git a/llvm/test/CodeGen/SystemZ/and-xor-01.ll b/llvm/test/CodeGen/SystemZ/and-xor-01.ll new file mode 100644 index 00000000000..f29c7d576d9 --- /dev/null +++ b/llvm/test/CodeGen/SystemZ/and-xor-01.ll @@ -0,0 +1,14 @@ +; Testing peephole for generating shorter code for (and (xor b, -1), a) +; +; RUN: llc < %s -mtriple=s390x-linux-gnu | FileCheck %s + +define i64 @f1(i64 %a, i64 %b) { +; CHECK-LABEL: f1: +; CHECK: ngr %r3, %r2 +; CHECK: xgr %r2, %r3 +; CHECK: br %r14 + %neg = xor i64 %b, -1 + %and = and i64 %neg, %a + ret i64 %and +} + |
