[llvm] [AMDGPU] Fix wrong MSB encoding for V_FMAMK instructions (PR #168107)

[Matt Arsenault via llvm-commits]

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@@ -3439,17 +3439,42 @@ getVGPRLoweringOperandTables(const MCInstrDesc &Desc) {
       AMDGPU::OpName::src0Y, AMDGPU::OpName::vsrc1Y, AMDGPU::OpName::vsrc2Y,
       AMDGPU::OpName::vdstY};
 
+  // VOP2 MADMK instructions use src0, imm, src1 scheme.
+  static const AMDGPU::OpName VOP2MADMKOps[4] = {
+      AMDGPU::OpName::src0, AMDGPU::OpName::imm, AMDGPU::OpName::src1,
+      AMDGPU::OpName::vdst};
+
   unsigned TSFlags = Desc.TSFlags;
 
   if (TSFlags &
       (SIInstrFlags::VOP1 | SIInstrFlags::VOP2 | SIInstrFlags::VOP3 |
        SIInstrFlags::VOP3P | SIInstrFlags::VOPC | SIInstrFlags::DPP)) {
+    switch (Desc.getOpcode()) {
     // LD_SCALE operands ignore MSB.
-    if (Desc.getOpcode() == AMDGPU::V_WMMA_LD_SCALE_PAIRED_B32 ||
-        Desc.getOpcode() == AMDGPU::V_WMMA_LD_SCALE_PAIRED_B32_gfx1250 ||
-        Desc.getOpcode() == AMDGPU::V_WMMA_LD_SCALE16_PAIRED_B64 ||
-        Desc.getOpcode() == AMDGPU::V_WMMA_LD_SCALE16_PAIRED_B64_gfx1250)
+    case AMDGPU::V_WMMA_LD_SCALE_PAIRED_B32:
+    case AMDGPU::V_WMMA_LD_SCALE_PAIRED_B32_gfx1250:
+    case AMDGPU::V_WMMA_LD_SCALE16_PAIRED_B64:
+    case AMDGPU::V_WMMA_LD_SCALE16_PAIRED_B64_gfx1250:
       return {};
+    case AMDGPU::V_FMAMK_F16_fake16_gfx11:
+    case AMDGPU::V_FMAMK_F16_fake16_gfx12:
+    case AMDGPU::V_FMAMK_F16_gfx10:
+    case AMDGPU::V_FMAMK_F16_t16_gfx11:
+    case AMDGPU::V_FMAMK_F16_t16_gfx12:
+    case AMDGPU::V_FMAMK_F32_gfx10:
+    case AMDGPU::V_FMAMK_F32_gfx11:
+    case AMDGPU::V_FMAMK_F32_gfx12:
+    case AMDGPU::V_FMAMK_F32_gfx940:
+    case AMDGPU::V_FMAMK_F64_gfx1250:
+    case AMDGPU::V_FMAMK_F16:
+    case AMDGPU::V_FMAMK_F16_t16:
+    case AMDGPU::V_FMAMK_F16_fake16:
+    case AMDGPU::V_FMAMK_F32:
----------------
arsenm wrote:

Test diff looks like only V_FMAMK_F32 is tested? 

https://github.com/llvm/llvm-project/pull/168107