[mips] For the FP64A ABI, odd-numbered double-precision moves must not use mtc1/mfc1.
Summary:
This is because the FP64A the hardware will redirect 32-bit reads/writes
from/to odd-numbered registers to the upper 32-bits of the corresponding
even register. In effect, simulating FR=0 mode when FR=0 mode is not
available.
Unfortunately, we have to make the decision to avoid mfc1/mtc1 before
register allocation so we currently do this for even registers too.
FPXX has a similar requirement on 32-bit architectures that lack
mfhc1/mthc1 so this patch also handles the affected moves from the FPU for
FPXX too. Moves to the FPU were supported by an earlier commit.
Differential Revision: http://reviews.llvm.org/D4484
llvm-svn: 212938
diff --git a/llvm/test/CodeGen/Mips/fpxx.ll b/llvm/test/CodeGen/Mips/fpxx.ll
index fb75e36..7e2ed22 100644
--- a/llvm/test/CodeGen/Mips/fpxx.ll
+++ b/llvm/test/CodeGen/Mips/fpxx.ll
@@ -11,38 +11,39 @@
; RUN: not llc -march=mips64 -mcpu=mips64 -mattr=fpxx < %s 2>&1 | FileCheck %s -check-prefix=64-FPXX
; RUN-TODO: llc -march=mips64 -mcpu=mips4 -mattr=-n64,+o32 < %s | FileCheck %s -check-prefix=ALL -check-prefix=4-O32-NOFPXX
-; RUN-TOOD: llc -march=mips64 -mcpu=mips4 -mattr=-n64,+o32 -mattr=fpxx < %s | FileCheck %s -check-prefix=ALL -check-prefix=4-O32-FPXX
+; RUN-TODO: llc -march=mips64 -mcpu=mips4 -mattr=-n64,+o32 -mattr=fpxx < %s | FileCheck %s -check-prefix=ALL -check-prefix=4-O32-FPXX
; RUN-TODO: llc -march=mips64 -mcpu=mips64 -mattr=-n64,+o32 < %s | FileCheck %s -check-prefix=ALL -check-prefix=64-O32-NOFPXX
-; RUN-TOOD: llc -march=mips64 -mcpu=mips64 -mattr=-n64,+o32 -mattr=fpxx < %s | FileCheck %s -check-prefix=ALL -check-prefix=64-O32-FPXX
+; RUN-TODO: llc -march=mips64 -mcpu=mips64 -mattr=-n64,+o32 -mattr=fpxx < %s | FileCheck %s -check-prefix=ALL -check-prefix=64-O32-FPXX
+declare double @dbl();
-; 4-FPXX: LLVM ERROR: FPXX is not permitted for the N32/N64 ABI's.
-; 64-FPXX: LLVM ERROR: FPXX is not permitted for the N32/N64 ABI's.
+; 4-FPXX: LLVM ERROR: FPXX is not permitted for the N32/N64 ABI's.
+; 64-FPXX: LLVM ERROR: FPXX is not permitted for the N32/N64 ABI's.
define double @test1(double %d, ...) {
ret double %d
; ALL-LABEL: test1:
-; 32-NOFPXX: mtc1 $4, $f0
-; 32-NOFPXX: mtc1 $5, $f1
+; 32-NOFPXX: mtc1 $4, $f0
+; 32-NOFPXX: mtc1 $5, $f1
; 32-FPXX: addiu $sp, $sp, -8
; 32-FPXX: sw $4, 0($sp)
; 32-FPXX: sw $5, 4($sp)
; 32-FPXX: ldc1 $f0, 0($sp)
-; 32R2-NOFPXX: mtc1 $4, $f0
-; 32R2-NOFPXX: mthc1 $5, $f0
+; 32R2-NOFPXX: mtc1 $4, $f0
+; 32R2-NOFPXX: mthc1 $5, $f0
-; 32R2-FPXX: mtc1 $4, $f0
-; 32R2-FPXX: mthc1 $5, $f0
+; 32R2-FPXX: mtc1 $4, $f0
+; 32R2-FPXX: mthc1 $5, $f0
; floats/doubles are not passed in integer registers for n64, so dmtc1 is not used.
-; 4-NOFPXX: mov.d $f0, $f12
+; 4-NOFPXX: mov.d $f0, $f12
-; 64-NOFPXX: mov.d $f0, $f12
+; 64-NOFPXX: mov.d $f0, $f12
}
define double @test2(i32 %i, double %d) {
@@ -50,23 +51,23 @@
; ALL-LABEL: test2:
-; 32-NOFPXX: mtc1 $6, $f0
-; 32-NOFPXX: mtc1 $7, $f1
+; 32-NOFPXX: mtc1 $6, $f0
+; 32-NOFPXX: mtc1 $7, $f1
; 32-FPXX: addiu $sp, $sp, -8
; 32-FPXX: sw $6, 0($sp)
; 32-FPXX: sw $7, 4($sp)
; 32-FPXX: ldc1 $f0, 0($sp)
-; 32R2-NOFPXX: mtc1 $6, $f0
-; 32R2-NOFPXX: mthc1 $7, $f0
+; 32R2-NOFPXX: mtc1 $6, $f0
+; 32R2-NOFPXX: mthc1 $7, $f0
-; 32R2-FPXX: mtc1 $6, $f0
-; 32R2-FPXX: mthc1 $7, $f0
+; 32R2-FPXX: mtc1 $6, $f0
+; 32R2-FPXX: mthc1 $7, $f0
-; 4-NOFPXX: mov.d $f0, $f13
+; 4-NOFPXX: mov.d $f0, $f13
-; 64-NOFPXX: mov.d $f0, $f13
+; 64-NOFPXX: mov.d $f0, $f13
}
define double @test3(float %f1, float %f2, double %d) {
@@ -74,23 +75,23 @@
; ALL-LABEL: test3:
-; 32-NOFPXX: mtc1 $6, $f0
-; 32-NOFPXX: mtc1 $7, $f1
+; 32-NOFPXX: mtc1 $6, $f0
+; 32-NOFPXX: mtc1 $7, $f1
; 32-FPXX: addiu $sp, $sp, -8
; 32-FPXX: sw $6, 0($sp)
; 32-FPXX: sw $7, 4($sp)
; 32-FPXX: ldc1 $f0, 0($sp)
-; 32R2-NOFPXX: mtc1 $6, $f0
-; 32R2-NOFPXX: mthc1 $7, $f0
+; 32R2-NOFPXX: mtc1 $6, $f0
+; 32R2-NOFPXX: mthc1 $7, $f0
-; 32R2-FPXX: mtc1 $6, $f0
-; 32R2-FPXX: mthc1 $7, $f0
+; 32R2-FPXX: mtc1 $6, $f0
+; 32R2-FPXX: mthc1 $7, $f0
-; 4-NOFPXX: mov.d $f0, $f14
+; 4-NOFPXX: mov.d $f0, $f14
-; 64-NOFPXX: mov.d $f0, $f14
+; 64-NOFPXX: mov.d $f0, $f14
}
define double @test4(float %f, double %d, ...) {
@@ -98,23 +99,23 @@
; ALL-LABEL: test4:
-; 32-NOFPXX: mtc1 $6, $f0
-; 32-NOFPXX: mtc1 $7, $f1
+; 32-NOFPXX: mtc1 $6, $f0
+; 32-NOFPXX: mtc1 $7, $f1
; 32-FPXX: addiu $sp, $sp, -8
; 32-FPXX: sw $6, 0($sp)
; 32-FPXX: sw $7, 4($sp)
; 32-FPXX: ldc1 $f0, 0($sp)
-; 32R2-NOFPXX: mtc1 $6, $f0
-; 32R2-NOFPXX: mthc1 $7, $f0
+; 32R2-NOFPXX: mtc1 $6, $f0
+; 32R2-NOFPXX: mthc1 $7, $f0
-; 32R2-FPXX: mtc1 $6, $f0
-; 32R2-FPXX: mthc1 $7, $f0
+; 32R2-FPXX: mtc1 $6, $f0
+; 32R2-FPXX: mthc1 $7, $f0
-; 4-NOFPXX: mov.d $f0, $f13
+; 4-NOFPXX: mov.d $f0, $f13
-; 64-NOFPXX: mov.d $f0, $f13
+; 64-NOFPXX: mov.d $f0, $f13
}
define double @test5() {
@@ -122,21 +123,99 @@
; ALL-LABEL: test5:
-; 32-NOFPXX: mtc1 $zero, $f0
-; 32-NOFPXX: mtc1 $zero, $f1
+; 32-NOFPXX: mtc1 $zero, $f0
+; 32-NOFPXX: mtc1 $zero, $f1
-; 32-FPXX: addiu $sp, $sp, -8
-; 32-FPXX: sw $zero, 0($sp)
-; 32-FPXX: sw $zero, 4($sp)
-; 32-FPXX: ldc1 $f0, 0($sp)
+; 32-FPXX: addiu $sp, $sp, -8
+; 32-FPXX: sw $zero, 0($sp)
+; 32-FPXX: sw $zero, 4($sp)
+; 32-FPXX: ldc1 $f0, 0($sp)
-; 32R2-NOFPXX: mtc1 $zero, $f0
-; 32R2-NOFPXX: mthc1 $zero, $f0
+; 32R2-NOFPXX: mtc1 $zero, $f0
+; 32R2-NOFPXX: mthc1 $zero, $f0
-; 32R2-FPXX: mtc1 $zero, $f0
-; 32R2-FPXX: mthc1 $zero, $f0
+; 32R2-FPXX: mtc1 $zero, $f0
+; 32R2-FPXX: mthc1 $zero, $f0
-; 4-NOFPXX: dmtc1 $zero, $f0
+; 4-NOFPXX: dmtc1 $zero, $f0
-; 64-NOFPXX: dmtc1 $zero, $f0
+; 64-NOFPXX: dmtc1 $zero, $f0
+}
+
+define double @test6(double %a, double %b, ...) {
+ %1 = fsub double %a, %b
+ ret double %1
+
+; ALL-LABEL: test6:
+
+; 32-NOFPXX-DAG: mtc1 $4, $[[T0:f[0-9]+]]
+; 32-NOFPXX-DAG: mtc1 $5, ${{f[0-9]*[13579]}}
+; 32-NOFPXX-DAG: mtc1 $6, $[[T1:f[0-9]+]]
+; 32-NOFPXX-DAG: mtc1 $7, ${{f[0-9]*[13579]}}
+; 32-NOFPXX: sub.d $f0, $[[T0]], $[[T1]]
+
+; 32-FPXX: addiu $sp, $sp, -8
+; 32-FPXX: sw $6, 0($sp)
+; 32-FPXX: sw $7, 4($sp)
+; 32-FPXX: ldc1 $[[T1:f[0-9]+]], 0($sp)
+; 32-FPXX: sw $4, 0($sp)
+; 32-FPXX: sw $5, 4($sp)
+; 32-FPXX: ldc1 $[[T0:f[0-9]+]], 0($sp)
+; 32-FPXX: sub.d $f0, $[[T0]], $[[T1]]
+
+; 32R2-NOFPXX-DAG: mtc1 $4, $[[T0:f[0-9]+]]
+; 32R2-NOFPXX-DAG: mthc1 $5, $[[T0]]
+; 32R2-NOFPXX-DAG: mtc1 $6, $[[T1:f[0-9]+]]
+; 32R2-NOFPXX-DAG: mthc1 $7, $[[T1]]
+; 32R2-NOFPXX: sub.d $f0, $[[T0]], $[[T1]]
+
+; 32R2-FPXX-DAG: mtc1 $4, $[[T0:f[0-9]+]]
+; 32R2-FPXX-DAG: mthc1 $5, $[[T0]]
+; 32R2-FPXX-DAG: mtc1 $6, $[[T1:f[0-9]+]]
+; 32R2-FPXX-DAG: mthc1 $7, $[[T1]]
+; 32R2-FPXX: sub.d $f0, $[[T0]], $[[T1]]
+
+; floats/doubles are not passed in integer registers for n64, so dmtc1 is not used.
+; 4-NOFPXX: sub.d $f0, $f12, $f13
+
+; floats/doubles are not passed in integer registers for n64, so dmtc1 is not used.
+; 64-NOFPXX: sub.d $f0, $f12, $f13
+}
+
+define double @move_from1(double %d) {
+ %1 = call double @dbl()
+ %2 = call double @test2(i32 0, double %1)
+ ret double %2
+
+; ALL-LABEL: move_from1:
+
+; 32-NOFPXX-DAG: mfc1 $6, $f0
+; 32-NOFPXX-DAG: mfc1 $7, $f1
+
+; 32-FPXX: addiu $sp, $sp, -32
+; 32-FPXX: sdc1 $f0, 16($sp)
+; 32-FPXX: lw $6, 16($sp)
+; FIXME: This store is redundant
+; 32-FPXX: sdc1 $f0, 16($sp)
+; 32-FPXX: lw $7, 20($sp)
+
+; 32R2-NOFPXX-DAG: mfc1 $6, $f0
+; 32R2-NOFPXX-DAG: mfhc1 $7, $f0
+
+; 32R2-FPXX-DAG: mfc1 $6, $f0
+; 32R2-FPXX-DAG: mfhc1 $7, $f0
+
+; floats/doubles are not passed in integer registers for n64, so dmfc1 is not used.
+; We can't use inline assembly to force a copy either because trying to force
+; a copy to a GPR this way fails with ; "couldn't allocate input reg for
+; constraint 'r'". It therefore seems impossible to test the generation of dmfc1
+; in a simple test.
+; 4-NOFPXX: mov.d $f13, $f0
+
+; floats/doubles are not passed in integer registers for n64, so dmfc1 is not used.
+; We can't use inline assembly to force a copy either because trying to force
+; a copy to a GPR this way fails with ; "couldn't allocate input reg for
+; constraint 'r'". It therefore seems impossible to test the generation of dmfc1
+; in a simple test.
+; 64-NOFPXX: mov.d $f13, $f0
}