; RUN: llc -verify-machineinstrs < %s -mtriple=aarch64-none-linux-gnu | FileCheck %s ; Transform "a == C ? C : x" to "a == C ? a : x" to avoid materializing C. ; CHECK-LABEL: test1: ; CHECK: cmp w[[REG1:[0-9]+]], #2 ; CHECK: orr w[[REG2:[0-9]+]], wzr, #0x7 ; CHECK: csel w0, w[[REG1]], w[[REG2]], eq define i32 @test1(i32 %x) { %cmp = icmp eq i32 %x, 2 %res = select i1 %cmp, i32 2, i32 7 ret i32 %res } ; Transform "a == C ? C : x" to "a == C ? a : x" to avoid materializing C. ; CHECK-LABEL: test2: ; CHECK: cmp x[[REG1:[0-9]+]], #2 ; CHECK: orr w[[REG2:[0-9]+]], wzr, #0x7 ; CHECK: csel x0, x[[REG1]], x[[REG2]], eq define i64 @test2(i64 %x) { %cmp = icmp eq i64 %x, 2 %res = select i1 %cmp, i64 2, i64 7 ret i64 %res } ; Transform "a != C ? x : C" to "a != C ? x : a" to avoid materializing C. ; CHECK-LABEL: test3: ; CHECK: cmp x[[REG1:[0-9]+]], #7 ; CHECK: orr w[[REG2:[0-9]+]], wzr, #0x2 ; CHECK: csel x0, x[[REG2]], x[[REG1]], ne define i64 @test3(i64 %x) { %cmp = icmp ne i64 %x, 7 %res = select i1 %cmp, i64 2, i64 7 ret i64 %res } ; Don't transform "a == C ? C : x" to "a == C ? a : x" if a == 0. If we did we ; would needlessly extend the live range of x0 when we can just use xzr. ; CHECK-LABEL: test4: ; CHECK: cmp x0, #0 ; CHECK: orr w8, wzr, #0x7 ; CHECK: csel x0, xzr, x8, eq define i64 @test4(i64 %x) { %cmp = icmp eq i64 %x, 0 %res = select i1 %cmp, i64 0, i64 7 ret i64 %res } ; Don't transform "a == C ? C : x" to "a == C ? a : x" if a == 1. If we did we ; would needlessly extend the live range of x0 when we can just use xzr with ; CSINC to materialize the 1. ; CHECK-LABEL: test5: ; CHECK: cmp x0, #1 ; CHECK: orr w[[REG:[0-9]+]], wzr, #0x7 ; CHECK: csinc x0, x[[REG]], xzr, ne define i64 @test5(i64 %x) { %cmp = icmp eq i64 %x, 1 %res = select i1 %cmp, i64 1, i64 7 ret i64 %res } ; Don't transform "a == C ? C : x" to "a == C ? a : x" if a == -1. If we did we ; would needlessly extend the live range of x0 when we can just use xzr with ; CSINV to materialize the -1. ; CHECK-LABEL: test6: ; CHECK: cmn x0, #1 ; CHECK: orr w[[REG:[0-9]+]], wzr, #0x7 ; CHECK: csinv x0, x[[REG]], xzr, ne define i64 @test6(i64 %x) { %cmp = icmp eq i64 %x, -1 %res = select i1 %cmp, i64 -1, i64 7 ret i64 %res } ; CHECK-LABEL: test7: ; CHECK: cmp x[[REG:[0-9]]], #7 ; CHECK: csinc x0, x[[REG]], xzr, eq define i64 @test7(i64 %x) { %cmp = icmp eq i64 %x, 7 %res = select i1 %cmp, i64 7, i64 1 ret i64 %res } ; CHECK-LABEL: test8: ; CHECK: cmp x[[REG:[0-9]]], #7 ; CHECK: csinc x0, x[[REG]], xzr, eq define i64 @test8(i64 %x) { %cmp = icmp ne i64 %x, 7 %res = select i1 %cmp, i64 1, i64 7 ret i64 %res } ; CHECK-LABEL: test9: ; CHECK: cmp x[[REG:[0-9]]], #7 ; CHECK: csinv x0, x[[REG]], xzr, eq define i64 @test9(i64 %x) { %cmp = icmp eq i64 %x, 7 %res = select i1 %cmp, i64 7, i64 -1 ret i64 %res } ; Rather than use a CNEG, use a CSINV to transform "a == 1 ? 1 : -1" to ; "a == 1 ? a : -1" to avoid materializing a constant. ; CHECK-LABEL: test10: ; CHECK: cmp w[[REG:[0-9]]], #1 ; CHECK: csinv w0, w[[REG]], wzr, eq define i32 @test10(i32 %x) { %cmp = icmp eq i32 %x, 1 %res = select i1 %cmp, i32 1, i32 -1 ret i32 %res }