[llvm] [AMDGPU][GlobalISel] Add RegBankLegalize support for G_FPTRUNC (PR #171723)

[via llvm-commits]

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@@ -736,6 +748,10 @@ define amdgpu_kernel void @fptrunc_v2f64_to_v2f32(ptr addrspace(1) %out, <2 x do
 ; GFX10-GISEL-NEXT:    v_cvt_f32_f64_e32 v0, s[0:1]
 ; GFX10-GISEL-NEXT:    v_cvt_f32_f64_e32 v1, s[2:3]
 ; GFX10-GISEL-NEXT:    s_load_dwordx2 s[0:1], s[4:5], 0x24
+; GFX10-GISEL-NEXT:    v_readfirstlane_b32 s2, v0
+; GFX10-GISEL-NEXT:    v_readfirstlane_b32 s3, v1
+; GFX10-GISEL-NEXT:    v_mov_b32_e32 v0, s2
+; GFX10-GISEL-NEXT:    v_mov_b32_e32 v1, s3
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vangthao95 wrote:

Done.

https://github.com/llvm/llvm-project/pull/171723