[llvm] [AMDGPU] MCExpr-ify AMDGPU HSAMetadata (PR #94788)

[Scott Linder via llvm-commits]

================
@@ -117,18 +119,19 @@ expr_defined:
 // ASM-NEXT: .amdhsa_system_sgpr_workgroup_id_z (((((((((((((((((((((((((((((((0&(~128))|(1<<7))&(~6144))|(defined_2_bits<<11))&(~128))|(defined_boolean<<7))&(~256))|(defined_boolean<<8))&(~512))|(defined_boolean<<9))&(~1024))|(defined_boolean<<10))&(~16777216))|(defined_boolean<<24))&(~33554432))|(defined_boolean<<25))&(~67108864))|(defined_boolean<<26))&(~134217728))|(defined_boolean<<27))&(~268435456))|(defined_boolean<<28))&(~536870912))|(defined_boolean<<29))&(~1073741824))|(defined_boolean<<30))&(~1))|(defined_boolean<<0))&(~62))|(0<<1))&512)>>9
 // ASM-NEXT: .amdhsa_system_sgpr_workgroup_info (((((((((((((((((((((((((((((((0&(~128))|(1<<7))&(~6144))|(defined_2_bits<<11))&(~128))|(defined_boolean<<7))&(~256))|(defined_boolean<<8))&(~512))|(defined_boolean<<9))&(~1024))|(defined_boolean<<10))&(~16777216))|(defined_boolean<<24))&(~33554432))|(defined_boolean<<25))&(~67108864))|(defined_boolean<<26))&(~134217728))|(defined_boolean<<27))&(~268435456))|(defined_boolean<<28))&(~536870912))|(defined_boolean<<29))&(~1073741824))|(defined_boolean<<30))&(~1))|(defined_boolean<<0))&(~62))|(0<<1))&1024)>>10
 // ASM-NEXT: .amdhsa_system_vgpr_workitem_id (((((((((((((((((((((((((((((((0&(~128))|(1<<7))&(~6144))|(defined_2_bits<<11))&(~128))|(defined_boolean<<7))&(~256))|(defined_boolean<<8))&(~512))|(defined_boolean<<9))&(~1024))|(defined_boolean<<10))&(~16777216))|(defined_boolean<<24))&(~33554432))|(defined_boolean<<25))&(~67108864))|(defined_boolean<<26))&(~134217728))|(defined_boolean<<27))&(~268435456))|(defined_boolean<<28))&(~536870912))|(defined_boolean<<29))&(~1073741824))|(defined_boolean<<30))&(~1))|(defined_boolean<<0))&(~62))|(0<<1))&6144)>>11
-// ASM-NEXT: .amdhsa_next_free_vgpr 0
-// ASM-NEXT: .amdhsa_next_free_sgpr 0
-// ASM-NEXT: .amdhsa_float_round_mode_32 (((((((((((((((((((((((((((((((0&(~786432))|(3<<18))&(~2097152))|(1<<21))&(~8388608))|(1<<23))&(~536870912))|(1<<29))&(~1073741824))|(1<<30))&(~12288))|(defined_2_bits<<12))&(~49152))|(defined_2_bits<<14))&(~196608))|(defined_2_bits<<16))&(~786432))|(defined_2_bits<<18))&(~67108864))|(defined_boolean<<26))&(~536870912))|(defined_boolean<<29))&(~1073741824))|(defined_boolean<<30))&(~2147483648))|(defined_boolean<<31))&(~63))|(0<<0))&(~960))|(0<<6))&12288)>>12
-// ASM-NEXT: .amdhsa_float_round_mode_16_64 (((((((((((((((((((((((((((((((0&(~786432))|(3<<18))&(~2097152))|(1<<21))&(~8388608))|(1<<23))&(~536870912))|(1<<29))&(~1073741824))|(1<<30))&(~12288))|(defined_2_bits<<12))&(~49152))|(defined_2_bits<<14))&(~196608))|(defined_2_bits<<16))&(~786432))|(defined_2_bits<<18))&(~67108864))|(defined_boolean<<26))&(~536870912))|(defined_boolean<<29))&(~1073741824))|(defined_boolean<<30))&(~2147483648))|(defined_boolean<<31))&(~63))|(0<<0))&(~960))|(0<<6))&49152)>>14
-// ASM-NEXT: .amdhsa_float_denorm_mode_32 (((((((((((((((((((((((((((((((0&(~786432))|(3<<18))&(~2097152))|(1<<21))&(~8388608))|(1<<23))&(~536870912))|(1<<29))&(~1073741824))|(1<<30))&(~12288))|(defined_2_bits<<12))&(~49152))|(defined_2_bits<<14))&(~196608))|(defined_2_bits<<16))&(~786432))|(defined_2_bits<<18))&(~67108864))|(defined_boolean<<26))&(~536870912))|(defined_boolean<<29))&(~1073741824))|(defined_boolean<<30))&(~2147483648))|(defined_boolean<<31))&(~63))|(0<<0))&(~960))|(0<<6))&196608)>>16
-// ASM-NEXT: .amdhsa_float_denorm_mode_16_64 (((((((((((((((((((((((((((((((0&(~786432))|(3<<18))&(~2097152))|(1<<21))&(~8388608))|(1<<23))&(~536870912))|(1<<29))&(~1073741824))|(1<<30))&(~12288))|(defined_2_bits<<12))&(~49152))|(defined_2_bits<<14))&(~196608))|(defined_2_bits<<16))&(~786432))|(defined_2_bits<<18))&(~67108864))|(defined_boolean<<26))&(~536870912))|(defined_boolean<<29))&(~1073741824))|(defined_boolean<<30))&(~2147483648))|(defined_boolean<<31))&(~63))|(0<<0))&(~960))|(0<<6))&786432)>>18
-// ASM-NEXT: .amdhsa_dx10_clamp (((((((((((((((((((((((((((((((0&(~786432))|(3<<18))&(~2097152))|(1<<21))&(~8388608))|(1<<23))&(~536870912))|(1<<29))&(~1073741824))|(1<<30))&(~12288))|(defined_2_bits<<12))&(~49152))|(defined_2_bits<<14))&(~196608))|(defined_2_bits<<16))&(~786432))|(defined_2_bits<<18))&(~67108864))|(defined_boolean<<26))&(~536870912))|(defined_boolean<<29))&(~1073741824))|(defined_boolean<<30))&(~2147483648))|(defined_boolean<<31))&(~63))|(0<<0))&(~960))|(0<<6))&2097152)>>21
-// ASM-NEXT: .amdhsa_ieee_mode (((((((((((((((((((((((((((((((0&(~786432))|(3<<18))&(~2097152))|(1<<21))&(~8388608))|(1<<23))&(~536870912))|(1<<29))&(~1073741824))|(1<<30))&(~12288))|(defined_2_bits<<12))&(~49152))|(defined_2_bits<<14))&(~196608))|(defined_2_bits<<16))&(~786432))|(defined_2_bits<<18))&(~67108864))|(defined_boolean<<26))&(~536870912))|(defined_boolean<<29))&(~1073741824))|(defined_boolean<<30))&(~2147483648))|(defined_boolean<<31))&(~63))|(0<<0))&(~960))|(0<<6))&8388608)>>23
-// ASM-NEXT: .amdhsa_fp16_overflow (((((((((((((((((((((((((((((((0&(~786432))|(3<<18))&(~2097152))|(1<<21))&(~8388608))|(1<<23))&(~536870912))|(1<<29))&(~1073741824))|(1<<30))&(~12288))|(defined_2_bits<<12))&(~49152))|(defined_2_bits<<14))&(~196608))|(defined_2_bits<<16))&(~786432))|(defined_2_bits<<18))&(~67108864))|(defined_boolean<<26))&(~536870912))|(defined_boolean<<29))&(~1073741824))|(defined_boolean<<30))&(~2147483648))|(defined_boolean<<31))&(~63))|(0<<0))&(~960))|(0<<6))&67108864)>>26
-// ASM-NEXT: .amdhsa_workgroup_processor_mode (((((((((((((((((((((((((((((((0&(~786432))|(3<<18))&(~2097152))|(1<<21))&(~8388608))|(1<<23))&(~536870912))|(1<<29))&(~1073741824))|(1<<30))&(~12288))|(defined_2_bits<<12))&(~49152))|(defined_2_bits<<14))&(~196608))|(defined_2_bits<<16))&(~786432))|(defined_2_bits<<18))&(~67108864))|(defined_boolean<<26))&(~536870912))|(defined_boolean<<29))&(~1073741824))|(defined_boolean<<30))&(~2147483648))|(defined_boolean<<31))&(~63))|(0<<0))&(~960))|(0<<6))&536870912)>>29
-// ASM-NEXT: .amdhsa_memory_ordered (((((((((((((((((((((((((((((((0&(~786432))|(3<<18))&(~2097152))|(1<<21))&(~8388608))|(1<<23))&(~536870912))|(1<<29))&(~1073741824))|(1<<30))&(~12288))|(defined_2_bits<<12))&(~49152))|(defined_2_bits<<14))&(~196608))|(defined_2_bits<<16))&(~786432))|(defined_2_bits<<18))&(~67108864))|(defined_boolean<<26))&(~536870912))|(defined_boolean<<29))&(~1073741824))|(defined_boolean<<30))&(~2147483648))|(defined_boolean<<31))&(~63))|(0<<0))&(~960))|(0<<6))&1073741824)>>30
-// ASM-NEXT: .amdhsa_forward_progress (((((((((((((((((((((((((((((((0&(~786432))|(3<<18))&(~2097152))|(1<<21))&(~8388608))|(1<<23))&(~536870912))|(1<<29))&(~1073741824))|(1<<30))&(~12288))|(defined_2_bits<<12))&(~49152))|(defined_2_bits<<14))&(~196608))|(defined_2_bits<<16))&(~786432))|(defined_2_bits<<18))&(~67108864))|(defined_boolean<<26))&(~536870912))|(defined_boolean<<29))&(~1073741824))|(defined_boolean<<30))&(~2147483648))|(defined_boolean<<31))&(~63))|(0<<0))&(~960))|(0<<6))&2147483648)>>31
+// ASM-NEXT: .amdhsa_next_free_vgpr defined_value+4
+// ASM-NEXT: .amdhsa_next_free_sgpr defined_value+5
+// ASM-NEXT: .amdhsa_reserve_vcc defined_boolean
+// ASM-NEXT: .amdhsa_float_round_mode_32 (((((((((((((((((((((((((((((((0&(~786432))|(3<<18))&(~2097152))|(1<<21))&(~8388608))|(1<<23))&(~536870912))|(1<<29))&(~1073741824))|(1<<30))&(~12288))|(defined_2_bits<<12))&(~49152))|(defined_2_bits<<14))&(~196608))|(defined_2_bits<<16))&(~786432))|(defined_2_bits<<18))&(~67108864))|(defined_boolean<<26))&(~536870912))|(defined_boolean<<29))&(~1073741824))|(defined_boolean<<30))&(~2147483648))|(defined_boolean<<31))&(~63))|((((alignto(max(defined_value+4, 1), 8))/8)-1)<<0))&(~960))|((((alignto(max(0, 1), 8))/8)-1)<<6))&12288)>>12
----------------
slinder1 wrote:

This may be coming a bit late, as the patch where these kinds of expressions were introduced is already landed, but is there a way to simplify these? We control how these pseudo-directives are defined, so it is at least feasible, right?

I know that hand-written assembler is "for experts", and that in this form it can act more as a symbolic relocatable, but one can end up with this form of build-the-whole-descriptor-and-then-locate-the-relevant-field expression in lieu of an error from something as trivial as a typo now, and when going to an object file you get no hints as to where the real root of the issue lies:

```
// whoops, meant the absolute value 0 here:
.amdhsa_next_free_sgpr a0

$ llvm-mc foo.s
<some unintelligible mess>
$ llvm-mc -filetype=obj foo.s
<unknown>:0: error: expected relocatable expression
```

Maybe we don't need to do anything, but it just feels "wrong" as-is.

https://github.com/llvm/llvm-project/pull/94788