[llvm] [RISCV][GISel] Attempt to simplify how we handle type legality for F and D extensions. (PR #72174)

[Craig Topper via llvm-commits]

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@@ -212,51 +221,26 @@ RISCVLegalizerInfo::RISCVLegalizerInfo(const RISCVSubtarget &ST) {
 
   getActionDefinitionsBuilder({G_FADD, G_FSUB, G_FMUL, G_FDIV, G_FMA, G_FNEG,
                                G_FABS, G_FSQRT, G_FMAXNUM, G_FMINNUM})
-      .legalIf([=, &ST](const LegalityQuery &Query) -> bool {
-        return (ST.hasStdExtF() && typeIs(0, s32)(Query)) ||
-               (ST.hasStdExtD() && typeIs(0, s64)(Query));
-      });
+      .legalIf(typeIsLegalScalarFP(0, ST));
 
   getActionDefinitionsBuilder(G_FPTRUNC).legalIf(
-      [=, &ST](const LegalityQuery &Query) -> bool {
-        return (ST.hasStdExtD() && typeIs(0, s32)(Query) &&
-                typeIs(1, s64)(Query));
-      });
+      all(typeIsLegalScalarFP(0, ST), typeIsLegalScalarFP(1, ST)));
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topperc wrote:

This is slighty different than the original logic. In RISC-V, hasStdExtD implies hasStdExtF and I assume a G_FPTRUNC where the source type isn't larger than the dest type is ill-formed. So I assume if the source type is legal and the dest type is legal the whole thing should be legal.

Same for G_FPEXT.

https://github.com/llvm/llvm-project/pull/72174