[PATCH] D107187: [amdgpu] Add an enhanced conversion from i64 to f32.

[Jay Foad via Phabricator via llvm-commits]

foad added inline comments.


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Comment at: llvm/lib/Target/AMDGPU/AMDGPUISelLowering.cpp:2456
                                                bool Signed) const {
   // Unsigned
   // cul2f(ulong u)
----------------
Can you rewrite this whole block comment to only describe what the code does now?


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Comment at: llvm/lib/Target/AMDGPU/AMDGPULegalizerInfo.cpp:2071
+  auto ThirtyTwo = B.buildConstant(S32, 32);
+  auto ThirtyThree = B.buildConstant(S32, 33);
 
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Move this inside the "if (Signed)" case.


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Comment at: llvm/test/CodeGen/AMDGPU/GlobalISel/cvt_f32_ubyte.ll:1085
 ; SI-NEXT:    s_waitcnt vmcnt(0) expcnt(0) lgkmcnt(0)
-; SI-NEXT:    s_movk_i32 s6, 0xff
-; SI-NEXT:    v_and_b32_e32 v0, s6, v0
-; SI-NEXT:    v_add_i32_e32 v0, vcc, 0, v0
-; SI-NEXT:    v_ffbh_u32_e32 v2, v0
-; SI-NEXT:    v_addc_u32_e64 v1, s[4:5], 0, 0, vcc
-; SI-NEXT:    v_add_i32_e32 v2, vcc, 32, v2
-; SI-NEXT:    v_ffbh_u32_e32 v3, v1
-; SI-NEXT:    v_cmp_eq_u32_e32 vcc, 0, v1
-; SI-NEXT:    v_cndmask_b32_e32 v2, v3, v2, vcc
-; SI-NEXT:    v_mov_b32_e32 v3, 0xbe
-; SI-NEXT:    v_sub_i32_e32 v4, vcc, v3, v2
-; SI-NEXT:    v_lshl_b64 v[2:3], v[0:1], v2
-; SI-NEXT:    v_cmp_ne_u64_e32 vcc, 0, v[0:1]
-; SI-NEXT:    v_and_b32_e32 v1, 0x7fffffff, v3
-; SI-NEXT:    v_cndmask_b32_e32 v0, 0, v4, vcc
-; SI-NEXT:    s_mov_b32 s4, 0
-; SI-NEXT:    v_and_b32_e32 v3, s6, v3
-; SI-NEXT:    s_movk_i32 s5, 0x80
-; SI-NEXT:    v_lshrrev_b32_e32 v1, 8, v1
-; SI-NEXT:    v_lshlrev_b32_e32 v0, 23, v0
-; SI-NEXT:    v_or_b32_e32 v0, v0, v1
-; SI-NEXT:    v_cmp_eq_u64_e32 vcc, s[4:5], v[2:3]
-; SI-NEXT:    v_and_b32_e32 v1, 1, v0
-; SI-NEXT:    v_cndmask_b32_e32 v1, 0, v1, vcc
-; SI-NEXT:    v_cmp_lt_u64_e32 vcc, s[4:5], v[2:3]
-; SI-NEXT:    v_cndmask_b32_e64 v1, v1, 1, vcc
-; SI-NEXT:    v_add_i32_e32 v0, vcc, v0, v1
+; SI-NEXT:    v_ffbh_i32_e32 v2, 0
+; SI-NEXT:    v_cmp_ne_u32_e32 vcc, -1, v2
----------------
Not related to your patch, but we should generate v_cvt_f32_ubyte0 here, shouldn't we?


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Comment at: llvm/test/CodeGen/AMDGPU/sint_to_fp.i64.ll:1
-; RUN: llc -march=amdgcn -verify-machineinstrs < %s | FileCheck --check-prefixes=GCN,FUNC %s
-; RUN: llc -march=amdgcn -mcpu=tonga -mattr=-flat-for-global -verify-machineinstrs < %s | FileCheck --check-prefixes=GCN,FUNC %s
+; RUN: llc -march=amdgcn -verify-machineinstrs < %s | FileCheck --check-prefixes=GCN,SI,FUNC %s
+; RUN: llc -march=amdgcn -mcpu=tonga -mattr=-flat-for-global -verify-machineinstrs < %s | FileCheck --check-prefixes=GCN,VI,FUNC %s
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Can you autogenerate the checks for this file and uint_to_fp.i64.ll and then rebase?


Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D107187/new/

https://reviews.llvm.org/D107187