[AMDGPU][MC] Don't accept attr > 32 for param_load

[rovka]

Summary

The docs say the interpolation attribute should be between 0..32 [1][2],
but we currently accept values all the way up to 63.

This patch makes the ASMParser error out for values > 32. It does not
touch codegen though because we're currently not checking anything at
all for codegen (llvm.amdgcn.lds.param.load will happily accept even 128
as an attr, although that won't fit in the encoding).

[1] https://llvm.org/docs/AMDGPU/gfx8_attr.html#amdgpu-synid-gfx8-attr
[2] https://llvm.org/docs/AMDGPU/gfx11_attr.html#amdgpu-synid-gfx11-attr

[foad]

LGTM, thanks!

llvm/lib/Target/AMDGPU/AsmParser/AMDGPUAsmParser.cpp

OperandMatchResultTy AMDGPUAsmParser::parseInterpAttr(OperandVector &Operands) {
   Str = Str.drop_back(2).drop_front(4);
 
   uint8_t Attr;
   if (Str.getAsInteger(10, Attr)) {
     Error(S, "invalid or missing interpolation attribute number");
     return MatchOperand_ParseFail;
   }
 
-  if (Attr > 63) {
+  if (Attr > 32) {
     Error(S, "out of bounds interpolation attribute number");
     return MatchOperand_ParseFail;
   }
 
   SMLoc SChan = SMLoc::getFromPointer(Chan.data());
 
   Operands.push_back(AMDGPUOperand::CreateImm(this, Attr, S,
                                               AMDGPUOperand::ImmTyInterpAttr));

llvm/test/MC/AMDGPU/gfx11_asm_ldsdir.s

 // GFX11: lds_param_load v9, attr4.w wait_vdst:7    ; encoding: [0x09,0x13,0x07,0xce]
 
 lds_param_load v10, attr11.x wait_vdst:6
 // GFX11: lds_param_load v10, attr11.x wait_vdst:6  ; encoding: [0x0a,0x2c,0x06,0xce]
 
 lds_param_load v11, attr22.y wait_vdst:5
 // GFX11: lds_param_load v11, attr22.y wait_vdst:5  ; encoding: [0x0b,0x59,0x05,0xce]
 
-lds_param_load v12, attr33.z wait_vdst:4
-// GFX11: lds_param_load v12, attr33.z wait_vdst:4  ; encoding: [0x0c,0x86,0x04,0xce]
-
-lds_param_load v13, attr63.x wait_vdst:3
-// GFX11: lds_param_load v13, attr63.x wait_vdst:3  ; encoding: [0x0d,0xfc,0x03,0xce]
-
-lds_param_load v14, attr63.y wait_vdst:2
-// GFX11: lds_param_load v14, attr63.y wait_vdst:2  ; encoding: [0x0e,0xfd,0x02,0xce]
-
-lds_param_load v15, attr63.z wait_vdst:1
-// GFX11: lds_param_load v15, attr63.z wait_vdst:1  ; encoding: [0x0f,0xfe,0x01,0xce]
-
-lds_param_load v16, attr63.w wait_vdst:0
-// GFX11: lds_param_load v16, attr63.w  ; encoding: [0x10,0xff,0x00,0xce]
-
-lds_param_load v17, attr63.w
-// GFX11: lds_param_load v17, attr63.w  ; encoding: [0x11,0xff,0x00,0xce]
+lds_param_load v12, attr32.z wait_vdst:4
+// GFX11: lds_param_load v12, attr32.z wait_vdst:4  ; encoding: [0x0c,0x82,0x04,0xce]

llvm/test/MC/AMDGPU/gfx11_asm_ldsdir_err.s

+// RUN: not llvm-mc -arch=amdgcn -mcpu=gfx1100 -show-encoding %s 2>&1 | FileCheck -check-prefix=GFX11 %s
+
+lds_param_load v17, attr33.x
+// GFX11: :[[@LINE-1]]:{{[0-9]+}}: error: out of bounds interpolation attribute number
+
+lds_param_load v17, attr33.y
+// GFX11: :[[@LINE-1]]:{{[0-9]+}}: error: out of bounds interpolation attribute number
+
+lds_param_load v17, attr33.z
+// GFX11: :[[@LINE-1]]:{{[0-9]+}}: error: out of bounds interpolation attribute number
+
+lds_param_load v17, attr33.w
+// GFX11: :[[@LINE-1]]:{{[0-9]+}}: error: out of bounds interpolation attribute number
+
+lds_param_load v12, attr33.z wait_va_vdst:4
+// GFX11: :[[@LINE-1]]:{{[0-9]+}}: error: out of bounds interpolation attribute number
+
+lds_param_load v12, attr33.w wait_va_vdst:2 wait_vm_vsrc:1
+// GFX11: :[[@LINE-1]]:{{[0-9]+}}: error: out of bounds interpolation attribute number
+

llvm/test/MC/AMDGPU/vintrp-err.s

 // RUN: not llvm-mc -arch=amdgcn %s 2>&1 | FileCheck -check-prefix=GCN --implicit-check-not=error: %s
 // RUN: not llvm-mc -arch=amdgcn -mcpu=tonga %s 2>&1 | FileCheck -check-prefix=GCN --implicit-check-not=error: %s
 
 v_interp_p1_f32 v0, v1
 // GCN: :[[@LINE-1]]:{{[0-9]+}}: error: too few operands for instruction
 
-v_interp_p1_f32 v0, v1, attr64.w
+v_interp_p1_f32 v0, v1, attr33.w
 // GCN: :[[@LINE-1]]:{{[0-9]+}}: error: out of bounds interpolation attribute number
 
-v_interp_p1_f32 v0, v1, attr64.x
+v_interp_p1_f32 v0, v1, attr33.x
 // GCN: :[[@LINE-1]]:{{[0-9]+}}: error: out of bounds interpolation attribute number
 
-v_interp_p2_f32 v9, v1, attr64.x
+v_interp_p2_f32 v9, v1, attr33.x
 // GCN: :[[@LINE-1]]:{{[0-9]+}}: error: out of bounds interpolation attribute number
 
-v_interp_p2_f32 v0, v1, attr64.x
+v_interp_p2_f32 v0, v1, attr33.x
 // GCN: :[[@LINE-1]]:{{[0-9]+}}: error: out of bounds interpolation attribute number
 
 v_interp_p2_f32 v0, v1, attr0.q
 // GCN: :[[@LINE-1]]:{{[0-9]+}}: error: invalid or missing interpolation attribute channel
 
 v_interp_p2_f32 v0, v1, attr0.
 // GCN: :[[@LINE-1]]:{{[0-9]+}}: error: invalid or missing interpolation attribute channel
 

llvm/test/MC/AMDGPU/vintrp.s

 v_interp_p1_f32 v8, v0, attr3.z
 // SI: v_interp_p1_f32 v8, v0, attr3.z ; encoding: [0x00,0x0e,0x20,0xc8]
 // VI: v_interp_p1_f32_e32 v8, v0, attr3.z ; encoding: [0x00,0x0e,0x20,0xd4]
 
 v_interp_p1_f32 v9, v0, attr4.w
 // SI: v_interp_p1_f32 v9, v0, attr4.w ; encoding: [0x00,0x13,0x24,0xc8]
 // VI: v_interp_p1_f32_e32 v9, v0, attr4.w ; encoding: [0x00,0x13,0x24,0xd4]
 
-v_interp_p1_f32 v10, v0, attr63.w
-// SI: v_interp_p1_f32 v10, v0, attr63.w ; encoding: [0x00,0xff,0x28,0xc8]
-// VI: v_interp_p1_f32_e32 v10, v0, attr63.w ; encoding: [0x00,0xff,0x28,0xd4]
+v_interp_p1_f32 v10, v0, attr32.w
+// SI: v_interp_p1_f32 v10, v0, attr32.w ; encoding: [0x00,0x83,0x28,0xc8]
+// VI: v_interp_p1_f32_e32 v10, v0, attr32.w ; encoding: [0x00,0x83,0x28,0xd4]
 
 
 v_interp_p2_f32 v2, v1, attr0.x
 // SI: v_interp_p2_f32 v2, v1, attr0.x ; encoding: [0x01,0x00,0x09,0xc8]
 // VI: v_interp_p2_f32_e32 v2, v1, attr0.x ; encoding: [0x01,0x00,0x09,0xd4]
 
 v_interp_p2_f32 v3, v1, attr0.y
 // SI: v_interp_p2_f32 v3, v1, attr0.y ; encoding: [0x01,0x01,0x0d,0xc8]

 v_interp_p2_f32 v6, v1, attr0.x
 // SI: v_interp_p2_f32 v6, v1, attr0.x ; encoding: [0x01,0x00,0x19,0xc8]
 // VI: v_interp_p2_f32_e32 v6, v1, attr0.x ; encoding: [0x01,0x00,0x19,0xd4]
 
 v_interp_p2_f32 v7, v1, attr1.x
 // SI: v_interp_p2_f32 v7, v1, attr1.x ; encoding: [0x01,0x04,0x1d,0xc8]
 // VI: v_interp_p2_f32_e32 v7, v1, attr1.x ; encoding: [0x01,0x04,0x1d,0xd4]
 
-v_interp_p2_f32 v8, v1, attr63.x
-// SI: v_interp_p2_f32 v8, v1, attr63.x ; encoding: [0x01,0xfc,0x21,0xc8]
-// VI: v_interp_p2_f32_e32 v8, v1, attr63.x ; encoding: [0x01,0xfc,0x21,0xd4]
+v_interp_p2_f32 v8, v1, attr32.x
+// SI: v_interp_p2_f32 v8, v1, attr32.x ; encoding: [0x01,0x80,0x21,0xc8]
+// VI: v_interp_p2_f32_e32 v8, v1, attr32.x ; encoding: [0x01,0x80,0x21,0xd4]
 
 
 v_interp_mov_f32 v0, p10, attr0.x
 // SI: v_interp_mov_f32 v0, p10, attr0.x ; encoding: [0x00,0x00,0x02,0xc8]
 // VI: v_interp_mov_f32_e32 v0, p10, attr0.x ; encoding: [0x00,0x00,0x02,0xd4]
 
 v_interp_mov_f32 v1, p20, attr0.x
 // SI: v_interp_mov_f32 v1, p20, attr0.x ; encoding: [0x01,0x00,0x06,0xc8]

 v_interp_mov_f32 v6, p10, attr0.w
 // SI: v_interp_mov_f32 v6, p10, attr0.w ; encoding: [0x00,0x03,0x1a,0xc8]
 // VI: v_interp_mov_f32_e32 v6, p10, attr0.w ; encoding: [0x00,0x03,0x1a,0xd4]
 
 v_interp_mov_f32 v7, p10, attr0.x
 // SI: v_interp_mov_f32 v7, p10, attr0.x ; encoding: [0x00,0x00,0x1e,0xc8]
 // VI: v_interp_mov_f32_e32 v7, p10, attr0.x ; encoding: [0x00,0x00,0x1e,0xd4]
 
-v_interp_mov_f32 v9, p10, attr63.y
-// SI: v_interp_mov_f32 v9, p10, attr63.y ; encoding: [0x00,0xfd,0x26,0xc8]
-// VI: v_interp_mov_f32_e32 v9, p10, attr63.y ; encoding: [0x00,0xfd,0x26,0xd4]
+v_interp_mov_f32 v9, p10, attr32.y
+// SI: v_interp_mov_f32 v9, p10, attr32.y ; encoding: [0x00,0x81,0x26,0xc8]
+// VI: v_interp_mov_f32_e32 v9, p10, attr32.y ; encoding: [0x00,0x81,0x26,0xd4]