[ARM] Correct features on pacbti tests. NFC

[dmgreen]

Summary

Given a patch like D129506, using instructions not valid for the current feature set becomes an error. This updates the Arm tests for pac/bti to use a thumbv8.1-m.main to make the instructions they produce valid. It requires altering some of the tests for the updated codegen.

[chill]

Is something breaking somewhere?
The compiler ought to generate valid PACBTI-M code for the v7-m architecture too, choosing only instructions from the NOP-space.

[dmgreen]

Oh I had that backwards then. The issue is that the instructions that it uses are all marked as requiring Armv8.1-m, so cannot be used validly in a Armv7-m build.

Should the instructions be available when assembling for thumbv7m? If so I can just change the predicates on the PACBTIHintSpaceInst instructions. If not they may need to use HINT's or use some pseudos.

[chill]

In D129692#3658852, @dmgreen wrote:

Oh I had that backwards then. The issue is that the instructions that it uses are all marked as requiring Armv8.1-m, so cannot be used validly in a Armv7-m build.

Should the instructions be available when assembling for thumbv7m? If so I can just change the predicates on the PACBTIHintSpaceInst instructions. If not they may need to use HINT's or use some pseudos.

Ideally, we would like mnemonics (for NOP-space instructions only) to be available in v-7m and up, even though they were introduced in v8.1-m.

[dmgreen]

Thanks - then this patch now sets the predicate on the Hint Space PACBTI instructions to thumbv7m. The test has been adjusted too, to show the instructions assembling/disassembling.

[chill]

LGTM, but let Victor take a look too.

[vhscampos]

It LGTM too. Thanks.

llvm/lib/Target/ARM/ARMInstrThumb2.td

 let isBranch = 1, isTerminator = 1, isIndirectBranch = 1 in {
   def t2BXAUT : PACBTIAut<(ins pred:$p, GPRnosp:$Ra, rGPR:$Rn, GPRnopc:$Rm),
                           "bxaut${p}", 1>;
 }
 }
 
 
 class PACBTIHintSpaceInst<string asm, string ops, bits<8> imm>
-  : V8_1MI<(outs), (ins), AddrModeNone, NoItinerary, asm, ops, "", []> {
+  : Thumb2XI<(outs), (ins), AddrModeNone, 4, NoItinerary, !strconcat(asm, "\t", ops), "", []>,
+    Requires<[HasV7, IsMClass]> {
   let Inst{31-8} = 0b111100111010111110000000;
   let Inst{7-0}  = imm;
 
   let Unpredictable{19-16} = 0b1111;
   let Unpredictable{13-11} = 0b101;
 
   let DecoderMethod = "DecodeT2HintSpaceInstruction";
 }

llvm/lib/Target/ARM/ARMScheduleA57.td

def CortexA57Model : SchedMachineModel {
 
   // Enable partial & runtime unrolling.
   let LoopMicroOpBufferSize = 16;
   let CompleteModel = 1;
 
   // FIXME: Remove when all errors have been fixed.
   let FullInstRWOverlapCheck = 0;
 
-  let UnsupportedFeatures = [HasV8_1MMainline, HasMVEInt, HasMVEFloat,
+  let UnsupportedFeatures = [HasV8_1MMainline, HasMVEInt, HasMVEFloat, IsMClass,
                              HasFPRegsV8_1M, HasFP16FML, HasMatMulInt8, HasBF16];
 }
 
 //===----------------------------------------------------------------------===//
 // Define each kind of processor resource and number available on Cortex-A57.
 // Cortex A-57 has 8 pipelines that each has its own 8-entry queue where
 // micro-ops wait for their operands and then issue out-of-order.
 

llvm/test/MC/ARM/armv8.1m-pacbti.s

-// RUN: llvm-mc -triple thumbv8.1m.main-arm-none-eabi -mattr=+pacbti %s -show-encoding -o - | FileCheck %s
-// RUN: not llvm-mc -triple thumbv8.1m.main-arm-none-eabi -mattr=-pacbti %s -show-encoding -o - 2>&1 | FileCheck %s --check-prefix=CHECK-NOPACBTI
+// RUN: llvm-mc -triple thumbv8.1m.main-arm-none-eabi -mattr=+pacbti %s -show-encoding -o - | FileCheck %s --check-prefixes=CHECK,CHECK-PACBTI
+// RUN: not llvm-mc -triple thumbv8.1m.main-arm-none-eabi -mattr=-pacbti %s -show-encoding -o - 2>&1 | FileCheck %s --check-prefixes=CHECK,CHECK-NOPACBTI
+// RUN: not llvm-mc -triple thumbv7m-arm-none-eabi %s -show-encoding -o - 2>&1 | FileCheck %s --check-prefixes=CHECK,CHECK-NOPACBTI
 
-// CHECK: autg  r0, r1, r2              @ encoding: [0x51,0xfb,0x02,0x0f]
+// Non Hint Space instructions and system regs
+
+// CHECK-PACBTI: autg r0, r1, r2             @ encoding: [0x51,0xfb,0x02,0x0f]
 // CHECK-NOPACBTI: error: instruction requires: pacbti
 autg r0, r1, r2
-// CHECK: autg  r12, lr, sp             @ encoding: [0x5e,0xfb,0x0d,0xcf]
+// CHECK-PACBTI: autg r12, lr, sp            @ encoding: [0x5e,0xfb,0x0d,0xcf]
 // CHECK-NOPACBTI: error: instruction requires: pacbti
 autg ip, lr, sp
-// CHECK: aut r12, lr, sp               @ encoding: [0xaf,0xf3,0x2d,0x80]
-aut ip, lr, sp
-// CHECK: aut r12,lr,sp               @ encoding: [0xaf,0xf3,0x2d,0x80]
-hint.w #45
-// CHECK: bxaut r0, r1, r2              @ encoding: [0x51,0xfb,0x12,0x0f]
+// CHECK-PACBTI: bxaut  r0, r1, r2             @ encoding: [0x51,0xfb,0x12,0x0f]
 // CHECK-NOPACBTI: error: instruction requires: pacbti
 bxaut r0, r1, r2
 
-// CHECK: bti                           @ encoding: [0xaf,0xf3,0x0f,0x80]
-bti
-// CHECK: bti                           @ encoding: [0xaf,0xf3,0x0f,0x80]
-hint.w #15
-
-// CHECK: pacg r0, r1, r2               @ encoding: [0x61,0xfb,0x02,0xf0]
+// CHECK-PACBTI: pacg r0, r1, r2               @ encoding: [0x61,0xfb,0x02,0xf0]
 // CHECK-NOPACBTI: error: instruction requires: pacbti
 pacg r0, r1, r2
-// CHECK: pacg r12, lr, sp              @ encoding: [0x6e,0xfb,0x0d,0xfc]
+// CHECK-PACBTI: pacg r12, lr, sp              @ encoding: [0x6e,0xfb,0x0d,0xfc]
 // CHECK-NOPACBTI: error: instruction requires: pacbti
 pacg ip, lr, sp
-// CHECK: pac r12, lr, sp               @ encoding: [0xaf,0xf3,0x1d,0x80]
-pac ip, lr, sp
-// CHECK: pac r12,lr,sp               @ encoding: [0xaf,0xf3,0x1d,0x80]
-hint.w #29
-// CHECK: pacbti r12, lr, sp            @ encoding: [0xaf,0xf3,0x0d,0x80]
-pacbti ip, lr, sp
-// CHECK: pacbti r12,lr,sp            @ encoding: [0xaf,0xf3,0x0d,0x80]
-hint.w #13
 
-// CHECK: msr pac_key_p_0, r0           @ encoding: [0x80,0xf3,0x20,0x88]
+// CHECK-PACBTI: msr  pac_key_p_0, r0           @ encoding: [0x80,0xf3,0x20,0x88]
 // CHECK-NOPACBTI: error: invalid operand for instruction
 msr pac_key_p_0, r0
-// CHECK: msr pac_key_p_1, r0           @ encoding: [0x80,0xf3,0x21,0x88]
+// CHECK-PACBTI: msr  pac_key_p_1, r0           @ encoding: [0x80,0xf3,0x21,0x88]
 // CHECK-NOPACBTI: error: invalid operand for instruction
 msr pac_key_p_1, r0
-// CHECK: msr pac_key_p_2, r0           @ encoding: [0x80,0xf3,0x22,0x88]
+// CHECK-PACBTI: msr  pac_key_p_2, r0           @ encoding: [0x80,0xf3,0x22,0x88]
 // CHECK-NOPACBTI: error: invalid operand for instruction
 msr pac_key_p_2, r0
-// CHECK: msr pac_key_p_3, r0           @ encoding: [0x80,0xf3,0x23,0x88]
+// CHECK-PACBTI: msr  pac_key_p_3, r0           @ encoding: [0x80,0xf3,0x23,0x88]
 // CHECK-NOPACBTI: error: invalid operand for instruction
 msr pac_key_p_3, r0
-// CHECK: msr pac_key_u_0, r0           @ encoding: [0x80,0xf3,0x24,0x88]
+// CHECK-PACBTI: msr  pac_key_u_0, r0           @ encoding: [0x80,0xf3,0x24,0x88]
 // CHECK-NOPACBTI: error: invalid operand for instruction
 msr pac_key_u_0, r0
-// CHECK: msr pac_key_u_1, r0           @ encoding: [0x80,0xf3,0x25,0x88]
+// CHECK-PACBTI: msr  pac_key_u_1, r0           @ encoding: [0x80,0xf3,0x25,0x88]
 // CHECK-NOPACBTI: error: invalid operand for instruction
 msr pac_key_u_1, r0
-// CHECK: msr pac_key_u_2, r0           @ encoding: [0x80,0xf3,0x26,0x88]
+// CHECK-PACBTI: msr  pac_key_u_2, r0           @ encoding: [0x80,0xf3,0x26,0x88]
 // CHECK-NOPACBTI: error: invalid operand for instruction
 msr pac_key_u_2, r0
-// CHECK: msr pac_key_u_3, r0           @ encoding: [0x80,0xf3,0x27,0x88]
+// CHECK-PACBTI: msr  pac_key_u_3, r0           @ encoding: [0x80,0xf3,0x27,0x88]
 // CHECK-NOPACBTI: error: invalid operand for instruction
 msr pac_key_u_3, r0
-// CHECK: msr pac_key_p_0_ns, r0        @ encoding: [0x80,0xf3,0xa0,0x88]
+// CHECK-PACBTI: msr  pac_key_p_0_ns, r0        @ encoding: [0x80,0xf3,0xa0,0x88]
 // CHECK-NOPACBTI: error: invalid operand for instruction
 msr pac_key_p_0_ns, r0
-// CHECK: msr pac_key_p_1_ns, r0        @ encoding: [0x80,0xf3,0xa1,0x88]
+// CHECK-PACBTI: msr  pac_key_p_1_ns, r0        @ encoding: [0x80,0xf3,0xa1,0x88]
 // CHECK-NOPACBTI: error: invalid operand for instruction
 msr pac_key_p_1_ns, r0
-// CHECK: msr pac_key_p_2_ns, r0        @ encoding: [0x80,0xf3,0xa2,0x88]
+// CHECK-PACBTI: msr  pac_key_p_2_ns, r0        @ encoding: [0x80,0xf3,0xa2,0x88]
 // CHECK-NOPACBTI: error: invalid operand for instruction
 msr pac_key_p_2_ns, r0
-// CHECK: msr pac_key_p_3_ns, r0        @ encoding: [0x80,0xf3,0xa3,0x88]
+// CHECK-PACBTI: msr  pac_key_p_3_ns, r0        @ encoding: [0x80,0xf3,0xa3,0x88]
 // CHECK-NOPACBTI: error: invalid operand for instruction
 msr pac_key_p_3_ns, r0
-// CHECK: msr pac_key_u_0_ns, r0        @ encoding: [0x80,0xf3,0xa4,0x88]
+// CHECK-PACBTI: msr  pac_key_u_0_ns, r0        @ encoding: [0x80,0xf3,0xa4,0x88]
 // CHECK-NOPACBTI: error: invalid operand for instruction
 msr pac_key_u_0_ns, r0
-// CHECK: msr pac_key_u_1_ns, r0        @ encoding: [0x80,0xf3,0xa5,0x88]
+// CHECK-PACBTI: msr  pac_key_u_1_ns, r0        @ encoding: [0x80,0xf3,0xa5,0x88]
 // CHECK-NOPACBTI: error: invalid operand for instruction
 msr pac_key_u_1_ns, r0
-// CHECK: msr pac_key_u_2_ns, r0        @ encoding: [0x80,0xf3,0xa6,0x88]
+// CHECK-PACBTI: msr  pac_key_u_2_ns, r0        @ encoding: [0x80,0xf3,0xa6,0x88]
 // CHECK-NOPACBTI: error: invalid operand for instruction
 msr pac_key_u_2_ns, r0
-// CHECK: msr pac_key_u_3_ns, r0        @ encoding: [0x80,0xf3,0xa7,0x88]
+// CHECK-PACBTI: msr  pac_key_u_3_ns, r0        @ encoding: [0x80,0xf3,0xa7,0x88]
 // CHECK-NOPACBTI: error: invalid operand for instruction
 msr pac_key_u_3_ns, r0
 
-// CHECK: mrs r0, pac_key_p_0           @ encoding: [0xef,0xf3,0x20,0x80]
+// CHECK-PACBTI: mrs  r0, pac_key_p_0           @ encoding: [0xef,0xf3,0x20,0x80]
 // CHECK-NOPACBTI: error: invalid operand for instruction
 mrs r0, pac_key_p_0
-// CHECK: mrs r0, pac_key_p_1           @ encoding: [0xef,0xf3,0x21,0x80]
+// CHECK-PACBTI: mrs  r0, pac_key_p_1           @ encoding: [0xef,0xf3,0x21,0x80]
 // CHECK-NOPACBTI: error: invalid operand for instruction
 mrs r0, pac_key_p_1
-// CHECK: mrs r0, pac_key_p_2           @ encoding: [0xef,0xf3,0x22,0x80]
+// CHECK-PACBTI: mrs  r0, pac_key_p_2           @ encoding: [0xef,0xf3,0x22,0x80]
 // CHECK-NOPACBTI: error: invalid operand for instruction
 mrs r0, pac_key_p_2
-// CHECK: mrs r0, pac_key_p_3           @ encoding: [0xef,0xf3,0x23,0x80]
+// CHECK-PACBTI: mrs  r0, pac_key_p_3           @ encoding: [0xef,0xf3,0x23,0x80]
 // CHECK-NOPACBTI: error: invalid operand for instruction
 mrs r0, pac_key_p_3
-// CHECK: mrs r0, pac_key_u_0           @ encoding: [0xef,0xf3,0x24,0x80]
+// CHECK-PACBTI: mrs  r0, pac_key_u_0           @ encoding: [0xef,0xf3,0x24,0x80]
 // CHECK-NOPACBTI: error: invalid operand for instruction
 mrs r0, pac_key_u_0
-// CHECK: mrs r0, pac_key_u_1           @ encoding: [0xef,0xf3,0x25,0x80]
+// CHECK-PACBTI: mrs  r0, pac_key_u_1           @ encoding: [0xef,0xf3,0x25,0x80]
 // CHECK-NOPACBTI: error: invalid operand for instruction
 mrs r0, pac_key_u_1
-// CHECK: mrs r0, pac_key_u_2           @ encoding: [0xef,0xf3,0x26,0x80]
+// CHECK-PACBTI: mrs  r0, pac_key_u_2           @ encoding: [0xef,0xf3,0x26,0x80]
 // CHECK-NOPACBTI: error: invalid operand for instruction
 mrs r0, pac_key_u_2
-// CHECK: mrs r0, pac_key_u_3           @ encoding: [0xef,0xf3,0x27,0x80]
+// CHECK-PACBTI: mrs  r0, pac_key_u_3           @ encoding: [0xef,0xf3,0x27,0x80]
 // CHECK-NOPACBTI: error: invalid operand for instruction
 mrs r0, pac_key_u_3
-// CHECK: mrs r0, pac_key_p_0_ns        @ encoding: [0xef,0xf3,0xa0,0x80]
+// CHECK-PACBTI: mrs  r0, pac_key_p_0_ns        @ encoding: [0xef,0xf3,0xa0,0x80]
 // CHECK-NOPACBTI: error: invalid operand for instruction
 mrs r0, pac_key_p_0_ns
-// CHECK: mrs r0, pac_key_p_1_ns        @ encoding: [0xef,0xf3,0xa1,0x80]
+// CHECK-PACBTI: mrs  r0, pac_key_p_1_ns        @ encoding: [0xef,0xf3,0xa1,0x80]
 // CHECK-NOPACBTI: error: invalid operand for instruction
 mrs r0, pac_key_p_1_ns
-// CHECK: mrs r0, pac_key_p_2_ns        @ encoding: [0xef,0xf3,0xa2,0x80]
+// CHECK-PACBTI: mrs  r0, pac_key_p_2_ns        @ encoding: [0xef,0xf3,0xa2,0x80]
 // CHECK-NOPACBTI: error: invalid operand for instruction
 mrs r0, pac_key_p_2_ns
-// CHECK: mrs r0, pac_key_p_3_ns        @ encoding: [0xef,0xf3,0xa3,0x80]
+// CHECK-PACBTI: mrs  r0, pac_key_p_3_ns        @ encoding: [0xef,0xf3,0xa3,0x80]
 // CHECK-NOPACBTI: error: invalid operand for instruction
 mrs r0, pac_key_p_3_ns
-// CHECK: mrs r0, pac_key_u_0_ns        @ encoding: [0xef,0xf3,0xa4,0x80]
+// CHECK-PACBTI: mrs  r0, pac_key_u_0_ns        @ encoding: [0xef,0xf3,0xa4,0x80]
 // CHECK-NOPACBTI: error: invalid operand for instruction
 mrs r0, pac_key_u_0_ns
-// CHECK: mrs r0, pac_key_u_1_ns        @ encoding: [0xef,0xf3,0xa5,0x80]
+// CHECK-PACBTI: mrs  r0, pac_key_u_1_ns        @ encoding: [0xef,0xf3,0xa5,0x80]
 // CHECK-NOPACBTI: error: invalid operand for instruction
 mrs r0, pac_key_u_1_ns
-// CHECK: mrs r0, pac_key_u_2_ns        @ encoding: [0xef,0xf3,0xa6,0x80]
+// CHECK-PACBTI: mrs  r0, pac_key_u_2_ns        @ encoding: [0xef,0xf3,0xa6,0x80]
 // CHECK-NOPACBTI: error: invalid operand for instruction
 mrs r0, pac_key_u_2_ns
-// CHECK: mrs r0, pac_key_u_3_ns        @ encoding: [0xef,0xf3,0xa7,0x80]
+// CHECK-PACBTI: mrs  r0, pac_key_u_3_ns        @ encoding: [0xef,0xf3,0xa7,0x80]
 // CHECK-NOPACBTI: error: invalid operand for instruction
 mrs r0, pac_key_u_3_ns
+
+// Hint space instructions - deliberately at the bottom of the file as the
+// error's are emitted first.
+
+// CHECK: aut r12, lr, sp             @ encoding: [0xaf,0xf3,0x2d,0x80]
+aut ip, lr, sp
+// CHECK: aut r12,lr,sp               @ encoding: [0xaf,0xf3,0x2d,0x80]
+hint.w #45
+
+// CHECK: bti                         @ encoding: [0xaf,0xf3,0x0f,0x80]
+bti
+// CHECK: bti                         @ encoding: [0xaf,0xf3,0x0f,0x80]
+hint.w #15
+
+// CHECK: pac r12, lr, sp               @ encoding: [0xaf,0xf3,0x1d,0x80]
+pac ip, lr, sp
+// CHECK: pac r12,lr,sp                 @ encoding: [0xaf,0xf3,0x1d,0x80]
+hint.w #29
+// CHECK: pacbti r12, lr, sp            @ encoding: [0xaf,0xf3,0x0d,0x80]
+pacbti ip, lr, sp
+// CHECK: pacbti r12,lr,sp              @ encoding: [0xaf,0xf3,0x0d,0x80]
+hint.w #13
 No newline at end of file