rjmccall added inline comments.
================
Comment at: clang/lib/CodeGen/CGExprComplex.cpp:934
+ return ComplexExprEmitter(*this).EmitPromoted(E, DstTy);
+}
+
----------------
rjmccall wrote:
> `EmitPromotedComplexExpr` should look like `EmitPromotedScalarExpr`, i.e. it
> should start with an expression, check for the arithmetic cases where we
> directly support promoted emission, and otherwise emit the unpromoted pair
> and then promote it.
Oh, I think I see how we're talking past each other. I keep telling you to
make this look like the scalar EmitPromoted, and now it does — but
unfortunately the scalar path is no longer correct, when I think it used to be.
Let me go suggest what the scalar path should look like.
================
Comment at: clang/test/CodeGen/X86/Float16-arithmetic.c:37
+ // CHECK: fptrunc float {{.*}} to half
+ // CHECK: ret half
+ return a + b + c;
----------------
Okay, you can't write tests like this. By using wildcards everywhere, you've
made this test so permissive that it failed to recognize that you had regressed
the basic truncation avoidance that's the whole point of this patch. You need
to write this like so:
```
CHECK: [[A:%.*]] = alloca half
CHECK: [[B:%.*]] = alloca half
...
CHECK: [[A_LOAD:%.*]] = load half, ptr [[A]],
CHECK: [[A_EXT:%.*]] = fpext half [[A_LOAD]] to float
CHECK: [[B_LOAD:%.*]] = load half, ptr [[B]],
CHECK: [[B_EXT:%.*]] = fpext half [[B_LOAD]] to float
CHECK: [[AB_ADD:%.*]] = fadd float [[A_EXT]], [[B_EXT]]
CHECK: [[C_LOAD:%.*]] = load half, ptr [[C]],
CHECK: [[C_EXT:%.*]] = fpext half [[C_LOAD]] to float
CHECK: [[ABC_ADD:%.*]] = fadd float [[AB_ADD]], [[C_EXT]]
```
And consider using `CHECK-NEXT` liberally as soon as you're out of the function
prologue and into the expression emission.
*All* of these tests need to be rewritten this way.
CHANGES SINCE LAST ACTION
https://reviews.llvm.org/D113107/new/
https://reviews.llvm.org/D113107
_______________________________________________
cfe-commits mailing list
cfe-commits@lists.llvm.org
https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
