[PATCH] D44519: Add llvm-exegesis tool.

[Clement Courbet via Phabricator via llvm-commits]

courbet added inline comments.


================
Comment at: tools/llvm-exegesis/lib/InstructionSnippetGenerator.cpp:151
+computeSequentialAssignmentChains(const llvm::MCRegisterInfo &RegInfo,
+                                  const llvm::ArrayRef<Variable> Vars) {
+  using graph::Node;
----------------
RKSimon wrote:
> Do you need the const on the ArrayRef? I don't think you can change anything - that's what MutableArrayRef is for.
Thanks for pointing that out.  Our internal ArrayRef (Span) can change its extent if not its elements. Fixed here and in 14 other places.


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Comment at: tools/llvm-exegesis/lib/InstructionSnippetGenerator.cpp:159
+  // Adding variables to the graph.
+  for (size_t I = 0; I < Vars.size(); ++I) {
+    const Variable &Var = Vars[I];
----------------
RKSimon wrote:
> ```
> for (size_t I = 0, E = Vars.size(); I < E; ++I) {
> ```
The compiler should be able to inline these, right ?


================
Comment at: tools/llvm-exegesis/lib/InstructionSnippetGenerator.cpp:230
+  // Registers with remaining degrees of freedom are assigned randomly.
+  for (size_t I = 0; I < Vars.size(); ++I) {
+    llvm::MCPhysReg &Reg = Registers[I];
----------------
RKSimon wrote:
> ```
> for (size_t I = 0, E = Vars.size(); I < E; ++I) {
> ```
ditto


================
Comment at: tools/llvm-exegesis/lib/Uops.cpp:101
+    // we never create a RAW hazard that would lead to serialization.
+    for (size_t I = 0; I < Vars.size(); ++I) {
+      llvm::MCPhysReg Reg = Regs[I];
----------------
RKSimon wrote:
> ```
> for (size_t I = 0, E = Vars.size(); I < e; ++I) {
> ```
ditto


Repository:
  rL LLVM

https://reviews.llvm.org/D44519