diff --git a/llvm/test/CodeGen/X86/reassociate-add.ll b/llvm/test/CodeGen/X86/reassociate-add.ll new file mode 100644 --- /dev/null +++ b/llvm/test/CodeGen/X86/reassociate-add.ll @@ -0,0 +1,125 @@ +; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py +; RUN: llc -mtriple=x86_64-unknown-unknown -mcpu=x86-64 < %s | FileCheck %s + +; This file checks the reassociation of ADD instruction. +; The two ADD instructions add v0,v1,t2 together. t2 has a long dependence +; chain, v0 and v1 has a short dependence chain, in order to get the shortest +; latency, v0 and v1 should be added first, and its result is added to t2 +; later. + +define void @add8(i8 %x0, i8 %x1, i8 %x2, i8* %p) { +; CHECK-LABEL: add8: +; CHECK: # %bb.0: +; CHECK-NEXT: orb $16, %dil +; CHECK-NEXT: orb $32, %sil +; CHECK-NEXT: addb $-8, %dl +; CHECK-NEXT: orb $7, %dl +; CHECK-NEXT: movzbl %dl, %eax +; CHECK-NEXT: imull $100, %eax, %eax +; CHECK-NEXT: addb %sil, %al +; CHECK-NEXT: addb %dil, %al +; CHECK-NEXT: movb %al, (%rcx) +; CHECK-NEXT: retq + %v0 = or i8 %x0, 16 + %v1 = or i8 %x1, 32 + %t0 = sub i8 %x2, 8 + %t1 = or i8 %t0, 7 + %t2 = mul i8 %t1, 100 + %t3 = add i8 %t2, %v1 + %t4 = add i8 %t3, %v0 + store i8 %t4, i8* %p, align 4 + ret void +} + +define void @add16(i16 %x0, i16 %x1, i16 %x2, i16* %p) { +; CHECK-LABEL: add16: +; CHECK: # %bb.0: +; CHECK-NEXT: orl $16, %edi +; CHECK-NEXT: orl $32, %esi +; CHECK-NEXT: addl $-8, %edx +; CHECK-NEXT: orl $7, %edx +; CHECK-NEXT: imull $100, %edx, %eax +; CHECK-NEXT: addl %esi, %eax +; CHECK-NEXT: addl %edi, %eax +; CHECK-NEXT: movw %ax, (%rcx) +; CHECK-NEXT: retq + %v0 = or i16 %x0, 16 + %v1 = or i16 %x1, 32 + %t0 = sub i16 %x2, 8 + %t1 = or i16 %t0, 7 + %t2 = mul i16 %t1, 100 + %t3 = add i16 %t2, %v1 + %t4 = add i16 %t3, %v0 + store i16 %t4, i16* %p, align 4 + ret void +} + +define void @add32(i32 %x0, i32 %x1, i32 %x2, i32* %p) { +; CHECK-LABEL: add32: +; CHECK: # %bb.0: +; CHECK-NEXT: orl $16, %edi +; CHECK-NEXT: orl $32, %esi +; CHECK-NEXT: addl $-8, %edx +; CHECK-NEXT: orl $7, %edx +; CHECK-NEXT: imull $100, %edx, %eax +; CHECK-NEXT: addl %esi, %eax +; CHECK-NEXT: addl %edi, %eax +; CHECK-NEXT: movl %eax, (%rcx) +; CHECK-NEXT: retq + %v0 = or i32 %x0, 16 + %v1 = or i32 %x1, 32 + %t0 = sub i32 %x2, 8 + %t1 = or i32 %t0, 7 + %t2 = mul i32 %t1, 100 + %t3 = add i32 %t2, %v1 + %t4 = add i32 %t3, %v0 + store i32 %t4, i32* %p, align 4 + ret void +} + +define void @add64(i64 %x0, i64 %x1, i64 %x2, i64* %p) { +; CHECK-LABEL: add64: +; CHECK: # %bb.0: +; CHECK-NEXT: orq $16, %rdi +; CHECK-NEXT: orq $32, %rsi +; CHECK-NEXT: addq $-8, %rdx +; CHECK-NEXT: orq $7, %rdx +; CHECK-NEXT: imulq $100, %rdx, %rax +; CHECK-NEXT: addq %rsi, %rax +; CHECK-NEXT: addq %rdi, %rax +; CHECK-NEXT: movq %rax, (%rcx) +; CHECK-NEXT: retq + %v0 = or i64 %x0, 16 + %v1 = or i64 %x1, 32 + %t0 = sub i64 %x2, 8 + %t1 = or i64 %t0, 7 + %t2 = mul i64 %t1, 100 + %t3 = add i64 %t2, %v1 + %t4 = add i64 %t3, %v0 + store i64 %t4, i64* %p, align 4 + ret void +} + +; Negative test. Original sequence has shorter latency, don't transform it. +define void @add64_negative(i64 %x0, i64 %x1, i64 %x2, i64* %p) { +; CHECK-LABEL: add64_negative: +; CHECK: # %bb.0: +; CHECK-NEXT: orq $16, %rdi +; CHECK-NEXT: orq $32, %rsi +; CHECK-NEXT: addq %rdi, %rsi +; CHECK-NEXT: addq $-8, %rdx +; CHECK-NEXT: orq $7, %rdx +; CHECK-NEXT: imulq $100, %rdx, %rax +; CHECK-NEXT: addq %rsi, %rax +; CHECK-NEXT: movq %rax, (%rcx) +; CHECK-NEXT: retq + %v0 = or i64 %x0, 16 + %v1 = or i64 %x1, 32 + %t0 = sub i64 %x2, 8 + %t1 = or i64 %t0, 7 + %t2 = mul i64 %t1, 100 + %t3 = add i64 %v0, %v1 + %t4 = add i64 %t3, %t2 + store i64 %t4, i64* %p, align 4 + ret void +}