[PATCH] D49754: Add -m(no-)spe, and e500 CPU definitions and support to clang

[Justin Hibbits via Phabricator via cfe-commits]

jhibbits added a comment.

Hi vit,

I found what's going on with the "Cannot Select" error.

divdc3.c contains code that gets lowered to a libcall.  However this lowering doesn't go further to lower down to the legal operations permitted in this target.

The debug snippet is:

Legalizing: t38: f64 = fmaxnum t36, t37, /home/chmeee/freebsd/contrib/compiler-rt/
lib/builtins/divdc3.c:24:22

  Op: t36: f64 = fabs t79, /home/chmeee/freebsd/contrib/compiler-rt/lib/builtins

/divdc3.c:24:22

  Op: t37: f64 = fabs t80, /home/chmeee/freebsd/contrib/compiler-rt/lib/builtins

/divdc3.c:24:22
Trying to expand node
Cannot expand node
Trying to convert node to libcall
Creating new node: t99: i64 = bitcast t36, /home/chmeee/freebsd/contrib/compiler-r
t/lib/builtins/divdc3.c:24:22
Creating new node: t100: i32 = extract_element t99, Constant:i32<1>, /home/chmeee/
freebsd/contrib/compiler-rt/lib/builtins/divdc3.c:24:22
Creating new node: t101: i32 = extract_element t99, Constant:i32<0>, /home/chmeee/
freebsd/contrib/compiler-rt/lib/builtins/divdc3.c:24:22
Creating new node: t102: i64 = bitcast t37, /home/chmeee/freebsd/contrib/compiler-
rt/lib/builtins/divdc3.c:24:22
Creating new node: t103: i32 = extract_element t102, Constant:i32<1>, /home/chmeee
/freebsd/contrib/compiler-rt/lib/builtins/divdc3.c:24:22
Creating new node: t104: i32 = extract_element t102, Constant:i32<0>, /home/chmeee
/freebsd/contrib/compiler-rt/lib/builtins/divdc3.c:24:22
Creating new node: t105: ch,glue = callseq_start t0, TargetConstant:i32<8>, Target
Constant:i32<0>, /home/chmeee/freebsd/contrib/compiler-rt/lib/builtins/divdc3.c:24
:22
Creating new node: t107: ch,glue = CopyToReg t105, Register:i32 $r3, t100, /home/c
hmeee/freebsd/contrib/compiler-rt/lib/builtins/divdc3.c:24:22
Creating new node: t108: ch,glue = CopyToReg t107, Register:i32 $r4, t101, t107:1,
 /home/chmeee/freebsd/contrib/compiler-rt/lib/builtins/divdc3.c:24:22
Creating new node: t110: ch,glue = CopyToReg t108, Register:i32 $r5, t103, t108:1,
 /home/chmeee/freebsd/contrib/compiler-rt/lib/builtins/divdc3.c:24:22
Creating new node: t112: ch,glue = CopyToReg t110, Register:i32 $r6, t104, t110:1,
 /home/chmeee/freebsd/contrib/compiler-rt/lib/builtins/divdc3.c:24:22
Creating new node: t114: ch,glue = PPCISD::CALL t112, TargetExternalSymbol:i32'fma
x' [TF=1], Register:i32 $r3, Register:i32 $r4, Register:i32 $r5, Register:i32 $r6,
 RegisterMask:Untyped, t112:1, /home/chmeee/freebsd/contrib/compiler-rt/lib/builti
ns/divdc3.c:24:22
Creating new node: t115: ch,glue = callseq_end t114, TargetConstant:i32<8>, Target
Constant:i32<0>, t114:1, /home/chmeee/freebsd/contrib/compiler-rt/lib/builtins/div
dc3.c:24:22
Creating new node: t116: i32,ch,glue = CopyFromReg t115, Register:i32 $r3, t115:1,
 /home/chmeee/freebsd/contrib/compiler-rt/lib/builtins/divdc3.c:24:22
Creating new node: t117: i32,ch,glue = CopyFromReg t116:1, Register:i32 $r4, t116:
2, /home/chmeee/freebsd/contrib/compiler-rt/lib/builtins/divdc3.c:24:22
Creating new node: t118: i64 = build_pair t117, t116, /home/chmeee/freebsd/contrib/compiler-rt/lib/builtins/divdc3.c:24:22
Creating new node: t119: f64 = bitcast t118, /home/chmeee/freebsd/contrib/compiler-rt/lib/builtins/divdc3.c:24:22
Created libcall: t119: f64 = bitcast t118, /home/chmeee/freebsd/contrib/compiler-rt/lib/builtins/divdc3.c:24:22
Successfully converted node to libcall
 ... replacing: t38: f64 = fmaxnum t36, t37, /home/chmeee/freebsd/contrib/compiler-rt/lib/builtins/divdc3.c:24:22

  with:      t119: f64 = bitcast t118, /home/chmeee/freebsd/contrib/compiler-rt/lib/builtins/divdc3.c:24:22

The last 3 lines are the key.  It's converting the node to a bitcast libcall, which ends up yielding a 'f64 bitcast (i64 build_pair i32, i32)', instead of lowering further to 'f64 build_spe64 i32, i32'.


Repository:
  rC Clang

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