cmd/compile/internal/inline: tweak "returns inlinable func" heuristic

[gostls13.git] / src / cmd / compile / internal / inline / inlheur / analyze_func_returns.go

diff --git a/src/cmd/compile/internal/inline/inlheur/analyze_func_returns.go b/src/cmd/compile/internal/inline/inlheur/analyze_func_returns.go
index e015961474c2a172c4fc04f3ad27ea82135b62b0..810714363192afd78c791877260ebd16b84aee62 100644 (file)
--- a/src/cmd/compile/internal/inline/inlheur/analyze_func_returns.go
+++ b/src/cmd/compile/internal/inline/inlheur/analyze_func_returns.go
@@ -16,10 +16,11 @@ import (
 // computing flags/properties for the return values of a specific Go
 // function, as part of inline heuristics synthesis.
 type returnsAnalyzer struct {
-       fname     string
-       props     []ResultPropBits
-       values    []resultVal
-       canInline func(*ir.Func)
+       fname           string
+       props           []ResultPropBits
+       values          []resultVal
+       canInline       func(*ir.Func)
+       inlineMaxBudget int32
 }
 
 // resultVal captures information about a specific result returned from
@@ -35,7 +36,7 @@ type resultVal struct {
        derived bool // see deriveReturnFlagsFromCallee below
 }
 
-func makeResultsAnalyzer(fn *ir.Func, canInline func(*ir.Func)) *returnsAnalyzer {
+func makeResultsAnalyzer(fn *ir.Func, canInline func(*ir.Func), inlineMaxBudget int32) *returnsAnalyzer {
        results := fn.Type().Results()
        props := make([]ResultPropBits, len(results))
        vals := make([]resultVal, len(results))
@@ -52,9 +53,10 @@ func makeResultsAnalyzer(fn *ir.Func, canInline func(*ir.Func)) *returnsAnalyzer
                vals[i].top = true
        }
        return &returnsAnalyzer{
-               props:     props,
-               values:    vals,
-               canInline: canInline,
+               props:           props,
+               values:          vals,
+               canInline:       canInline,
+               inlineMaxBudget: inlineMaxBudget,
        }
 }
 
@@ -74,7 +76,14 @@ func (ra *returnsAnalyzer) setResults(fp *FuncProps) {
                                        ra.canInline(f)
                                }
                        }
-                       if f.Inl != nil {
+                       // HACK: in order to allow for call site score
+                       // adjustments, we used a relaxed inline budget in
+                       // determining inlinability. Here what we want to know is
+                       // whether the func in question is likely to be inlined,
+                       // as opposed to whether it might possibly be inlined if
+                       // all the right score adjustments happened, so check the
+                       // cost here as well.
+                       if f.Inl != nil && f.Inl.Cost <= ra.inlineMaxBudget {
                                ra.props[i] = ResultAlwaysSameInlinableFunc
                        }
                }